test: add rilmodem specific tests

Add rilmodem directory and tests to be used both for
daily and CI testing.  Some of these tests are only
meant to be run within the touch emulator, as they
rely on the emulator console commands in order to
change the state of the mocked modem.
test: enhanced rilmodem/test-sim-online script

Enhanced the test-sim-online script so that you can
specify if the script is running in the emulator,
optionally cause the script to online the modem, and
finally if running on real hw, specify specific property
values to match against.
test: Cleanup TODO comments in rilmodem tests
test: cleanup rilmodem review style comments
build: add rilmodem tests to build
Merge pull request #46 from tonyespy/rilmodem-test

Rilmodem test