Add new shelve compute feature flag

Shelving/unshelving is not supported across all drivers (e.g., Ironic).
This adds a new compute feature flag and skips tests where this function
is performed.

Change-Id: Ib94b479db2b691e73c6121c17cb47ae1c25636a8
Sahara: preparations for job tests

* create/list/get/delete methods to Sahara API client for jobs
  were added
* Method "create_job" was added
* tearDownClass method was expanded

Partially implements: blueprint savanna-api-tests

Change-Id: I8d52a7505aeb25b7de3f6c8479daa056b8c6eae7
Sahara: add API tests for jobs

* create/list/get/delete API tests for jobs were added

Implements: blueprint savanna-api-tests

Change-Id: I8110f4e62c6934967aa316a7027987390d5135a8
Set python hash seed to 0 in tox.ini

New tox (>=1.7.0) sets a random python hash seed by default. This is
generally good for testing because it will help keep projects working
regardless of the hash seed, but tempest unittests don't currently
pass a with a random hash seed so set it to the python default seed.

This change will allow us to use new tox again and remove the
restriction on tox<=1.6.1 to run unittests.

Change-Id: Ib54364877a251db48c54dfdc43c503281ea1f04a
Merge "Sahara: preparations for job tests"
Merge "Set python hash seed to 0 in tox.ini"
Merge "Add new shelve compute feature flag"
Merge "Sahara: add API tests for jobs"