[TEST] Added ability to skip REST test suite/sections based on their required features

As we have different runners for the REST tests we need a mechanism that allows us to add features to any of them without breaking all others builds.
The idea is to name a feature and temporarily use skip sections that mention the required new features, so that runners that don't support it will skip the test.

Added support for `features` field in skip section.
Added `Features` class that contains a static list of the features supported by the runner. If a feature mentioned in a skip section is not listed here, the test will be skipped.
[TEST] clarified skip features usage