Make the osquery extension and runner separate rungroups

[RebeccaMahany]

Relates to #1473

Currently, we have an actorQuerier rungroup wrapper around both the extension and the runner, which act as a semi-conjoined single rungroup. They don't need to be coupled like this: the extension doesn't need the runner (since we officially disabled the initial runner), and the runner doesn't need the extension (it just needs a couple opts passed in to register the extension correctly when creating the osquery instance). My hope is that decoupling them will make it easier for us to handle the "unenrolled" state and give us better flexibility for how we want to do that. I also think it'll make rewriting our rungroups easier in the future, too.

This PR makes the following changes:

• Makes the runner and the extension both adhere to the rungroup actor interface
• Decouples the runner and the extension
• Removes support for osquery transport method (we don't really use it and haven't for a while)
• Removes unused initial runner
• Gives the runner access to the knapsack
• Gives the runner access to its own slogger instead of having to reach into the instance to use its logger

Testing notes

• launcher can start up osquery successfully
• launcher will restart osquery if the process is manually killed
• can query kolide_ tables provided by the extension
• enrollment works
• logs show up with component osquery_runner and osquery_extension as expected

[James-Pickett]

nice, this is much cleaner!

[zackattack01]

looks great! 🔥

[RebeccaMahany]

Will merge this after we declare v1.5.3 stable