… of thumbnail. Also refactors mediaReducer.media.

refactor: refactors away alot of duplication in mediaReducer.media.
feature: adds 'isHidden' to IThumbnail.
feature: adds 'isHidingState' to IOutput.
feature: adds handling of dispatching to redux store when Hiding state updates.
chore: renames 'LOOP_STATEUPDATE' to 'LOOP_STATE_UPDATE' to match other similar ones.

feature: adds the 'Hiding' button to the UI.
feature: adds a handful of missing redux store dispatches in connection with the new feature being developed.
feature: adds a handful of missing event listeners in connection with the new feature being developed.
feature: adds missing default values for the settings being stored in connection with the new feature being developed.
chore: adjusted name of of constant(s) for hiding, to use use boolean indicative pattern (IS_<X>).
refactor: refactors settingsReducer.settings to only have one return statement.
fix: fixes a few areas that wasn't renamed successfully from renaming in the the previous commit.

chore: renames new constants to match the pattern established by the existing constants.
feature: begins on adding temporary console.log statements to track down why the new button doesn't toggle.

fix: fixes incorrect name of property accessed on 'any' type causing the button to not toggle.
chore: removes all console.log's used to track down why it wasn't toggling.
chore: renames more properties to get in line with the pattern established by other similar properties.

chore: renames anything to do with 'Hide' yet again, to use 'Visibility' instead.
refactor: simplifies 'conditionalApplyAction' into new method 'doesChannelExist', to handle the reduced duplication more cleanly.
refactor: makes use of result from `useSelector(...)` instead of requesting the same data, the following line.
	- this also cuts down on the code size in many places where it was gotten twice.
refactor: converts a large if/else into a much simpler ternary operator.
	- this was one of the main beneficiaries from the `useSelector(...)` change.
refactor: adds types to many 'props' inside Thumbnail.tsx
feature: extracts current file being interacted with during click event in Thumbnail.tsx

feature: makes onClick of Thumbnail perform different action depending on if in 'edit visibility' mode
feauture: adds new events to handle toggling a thumbnails visibility.
refactor: extracts commonality between interfaces out to a common shared interface.
refactor: adds types to previously 'any' type.
chore: changes comparison used for UT-205 to use '===' instead of '.match'
fix: fixes some areas that was missed when renaming previously.

feature: adds saving of hiddenFiles as a json file to persist between sessions.
chore: eliminates the sideeffect of 'toggleHiddenFile' by copying the record, deleting from it, then returning it.
fix: fixes apparent long standing bug that doesn't appear to have had any negative impact.

…enFiles when backing file is altered.

refactor: reworks 'visibilityState' into 'operationMode'
refactor: renames yet again just about anything with 'visibility' to something with 'operation'.
feature: adds 'operationMode' enum, allowing easier expansion in the future.
refactor: changes 'handleClickMedia' to use a switch rather than a ternary operator, to decide performed action.
chore: renames 'onClickPlayClicked' to 'playFile'.
chore: renames 'onClickToggleVisibility' to 'toggleVisibility'.
chore: renames 'IChangedInfo' to 'IHiddenFileInfo'
chore: moves 'size' from ICommonFile to IHiddenFileInfo.
feature: adds check to prevent hidding of currently playing file.
chore: adds types to a few places.
chore: extracts props type used multiple places in Thumbnail.tsx to an interface.
chore: renames 'item' to 'file'.
fix: fixes thumbnail not updating when backing file's thumbnail has changed.

…eview.

feature: adds Footer, giving clear indication that a different operation mode is in effect.
feature: improves application styling to fill screen better, to also place Footer truely at the bottom.
refactor: moves styling created inline to CSS files.
chore: removes unnecessary arrow function for onClick handlers.

feature: adds a button to the footer that exits whichever mode you are in back to OperationMode.Control always.
refactor: moves the new hiding button to be under settings, insted of the topbar.
chore: updated color of footer text to better represent a warning, rather than an error. (orangeish color vs redish color)

chore: shrinks hasThumbListChanged(...) by usng function on array.
chore: extracts innards of Footer to another component, to eliminate nested ternaries

…utputs.

refactor: moves hiddenFiles from IMedia to IOutput.
refactor: reworks loadHiddenFiles to split the saved array out to the outputs.
refactor: moves call to loadHiddenFiles to just before initializing client in socketIOServerHandler.
refactor: adds channelIndex as input to updateHiddenFiles

…ltiple outputs."

This reverts commit 0bcd958.

# Conflicts:
#	src/client/components/Thumbnail.tsx

…every hidden file inside one record.

refactor: moves Footer.tsx to new subfolder 'Footer'.
refactor: extract FooterContent component to its own file.
refactor: created 'EditVisibilityFooter' to cut away the use of a map for different text depending on operationMode.

refactor: adds return type to a few functions.
refactor: changes a few functions defined as constants with arrow functions, into function definitions.
chore: adds nullish coalescing to a number of 'useSelector(...)'.
chore: updates the order of import in App.tsx.
style: solidifies border-width and makes the color the thing that changes on selecting a file.
refactor: fixes a typo in a css class name.

refactor: changes the text show on the button to go into 'EDIT VISIBILITY' mode.
refactor: split up toggleHiddenFile function to better get in line with single responsibility.
refactor: extracted logic to figuring out the current active output to a function.
	note: could possibly be moved to a more centralized location, and be reused more places.
refactor: changes retrival of active output to use new function in all of Thumbnail.tsx.
refactor: extracted code to find file to its own function in socketIOServerHandler.
refactor: adds a logger log, with data, incase toggling the hidden state fails.

refactor: renames a few constants to use SNAKE_CASE.
refactor: renames a function to a more generic name.
chore: changes use of double quotes for string to single quotes a few places.
refactor: adds a better type than 'any' to a few places.

refactor: renames 'findThumbPix' to 'findThumbnail'.
refactor: removes export on 'isThumbWithTally'.
refactor: renames 'IHiddenFileInfo' to 'HiddenFileInfo'.
refactor: renames 'IThumbFile' to 'IThumbnailFile'.
refactor: adds some types to better describe what is being manipulated.
style: removes some css that had no visual effect from what i could tell.

…or of .some(...).

…einplementTabs.