Run CTS verifier sensor tests only when there is a sensor

Add a new meta data attribute tests_applicable_features to
conditionally include tests when at least one of a list of
features are available.

Update sensor test to only show up when at least one of the
sensors being tested exists on the device

Bug: 18285373
Change-Id: I409d8605c6abc66d70d17afb36400e9d1ba2a813
3 files changed