Merge branch 'feature/idf_monitor' into 'master'

Merge branch 'feature/idf_monitor' into 'master'

Expand  'make monitor' support

New 'make monitor' idf_monitor tool for better monitor output. Running 'make monitor' will now:
* Automatically look up code addresses via addr2line and print function, source file, line number in terminal.
* Can reset the ESP32 by typing Ctrl-T Ctrl-R.
* Can run "make flash" by typing Ctrl-T Ctrl-F.
* Can run "make app-flash" by typing Ctrl-T Ctrl-A.
* If gdb stub starts, monitor will automatically run gdb and connect. When gdb exits, ESP32 resets and monitor resumes.
* Exit is still Ctrl-[

Have some more features I'd like to add (log output to file, crash dump support) but I think this is at the point of being useful.

See merge request !565