feat(mdtest run): support device matching and test script automation

Automatically match each device spec with an available device, then
launch applications on devices based on the matching.  After all
applications are correctly installed and launched, run test script
which automates the UI.  mdtest requires the user to use its
driver/driver_util.dart to create flutter driver.

Change-Id: Ib3b895dd162ca5584b2a208dedaaed6535ed91c2
6 files changed