Escape Hyphens in Function Names for AppSettings

[davidmrdavid]

Discussion for: #1942

[brettsam]

Questions from discussion:

• Is the proposal that the Portal always escapes? Does the Portal need to know that it can only do this in v4?
  • Portal could try/catch around setting the value. If it fails, retry with an escaped function name.
• What if, instead, we had a single key like DisabledFunctions -- with a semi-colon disabled list of disabled Functions?
  • Would need to support both models in v3. And determine what happens if there is conflicting detail between the two?
  • However, This would be adding yet another way to disable functions, which would be hard to manage.
• Components impacted should include Portal (or possibly the management API operation). If this is all behind an API, then checking version could be simpler.
• Does ScaleController need work here to support enable/disable?
• We should be able to backport this to v3 to simplify the matrix of support.
• Need to define the escape char in Linux. This requires some research. @davidmrdavid to investigate.

Approving this -- but finding the escape sequence that works on Windows and Linux is still required.

This does not constitute a breaking change, so we can remove this from the breaking change list and fix it in v3 and v4 whenever we want.