Improved the rack concept, added OysterBay, tests.

Added OysterBayPxtDevelopmentRack which inherits from
RackWithLteAndDataSourceBase. These classes hold the
constituents of the rack, as well as what steps are
needed to initialize them.

Added RackWithLteAndHspa3GAndDataSourceBase as a
prototype to illustrate a Rack with more than one
call box.

BUG=chromium:272493
TEST=run_all_tests.py

Change-Id: Icab1dafe5c6773b2394bd6585b3f660d38381fe8
Reviewed-on: https://chromium-review.googlesource.com/182865
Reviewed-by: Prathmesh Prabhu <pprabhu@chromium.org>
Commit-Queue: Byron Kubert <byronk@chromium.org>
Tested-by: Byron Kubert <byronk@chromium.org>
5 files changed