FakeApp.app should include a CFBundleIdentifier
add retry logic around ios app install and uninstall.

Squashed from:
task/2505957: Add run retries. 'N of N tests passed' still displayed on failure
Add 'retry' notice upon failure
Clean up messaging and add some color
Placed retry logic in pkg install/uninstall branches
Change var names to be accurate
moving app uninstall and install routines into their own methods.

`runTestsAndFeedOutputTo:...` was getting too long.
reworking the control flow in the app install / uninstall methods.

It's functionally equivalent to the former code, except if something
fails all retries, we'll return NO.

I found the earlier do/while code a little tricky to follow.