Use environment for appName and replace hardcoded Loop with appName

[marionbarker]

1. Add code needed to use environment that ties appName to CFBundleDisplayName
2. Replace the hard-coded "Loop" string with appName

Test:

• Only two files use appName
  • The UncertainRecovery display was not tested (the OmniBLE version was)
  • The BeepPreference updates with the string appName in the file but I could not figure out how to get the environment variable included.

[marionbarker]

The open PR 32 will modify some of these strings. Hold off on this for now.
Note to self - update for appName

• BeepPreference.swift

Edited because PR 32 is now merged.

[marionbarker]

I believe this PR is good enough. The Uncertainty Recovery view should reflect appName (tested with OmniBLE, but not OmniKit). I was not able to solve the problem for BeepPreference, but used the same work-around as was used for OmniBLE.

The screen with this PR applied is identical to that seen in OmniBLE PR 120 in this comment:

• Use environment for appName and replace hardcoded Loop with appName OmniBLE#120 (comment)