Regex float parameters docs

[kcormi]

This is adding some minor documentation to make it clear that regex are also available for the --floatParameters option, as per #851.

I've simply separated the documentation so that it is updated on the next recommended version update, and not before. This branch should be merged when we make that change.

[kcormi]

I've also added a minor documentation update for ChannelCompatibilityCheck to document the -g option in the online docs and the ability to set ranges for individual POIs via this option, as in #760

[nucleosynthesis]

All looks good to me, I think we can merge this one

[anigamova]

Perhaps we should wait with this PR until we are ready to release a new version, this feature is not available in v9.1 yet

[nucleosynthesis]

Hi @kcormi - looks like we now have conflicts after the checks from Adinda. Can you see if those can be fixed and we go ahead and merge this?

[kcormi]

I've just resolved the conflicts, I think it should be fine to merge now, which we can do whenever we make the new release.

[nucleosynthesis]

I'll merge this one now, to make sure its in for the next Tag