images api v1.0 functional tests (tempest parity)

Depends on:
Change-Id: I5992df42cc3513aeedf3576b6884e357ac088622

 - removed deprecated image/ folder
 - modified folder structure as per discussion with Nandhini
 - removed ImageV2Client, dependency on a forward-patch that wouldn't
   let this one run tests.
 - fixed hanging parenthesis
 - some style changes
 - completed tempest test parity for this set of tests
 - rename image/ to images/
 - improve fixture

Change-Id: I04d39b9c1ef3902dbe36c0d1535a370f5fd5e57b
extend functional tests

Depends on:
Change-Id: I86a280cf3d186876da9dbd44c8099aac87cf56c3

 - now testing for disjoint sets in ListImagesTest instead of previous
   shenanigans.
 - rebased with master and split tests into separate modules
 - moved _setup_test_data as a fixture for ListImagesTest
 - removed unused imports
 - refactored Image model to use renamed property id_
 - rebase and removed hardcoded urls
 - added more tests to be on par with tempest

Change-Id: If3346371a0e3e43490cad0f322f7913a64a3fd8f
Temporarily removing invalid reference to V2Client

Change-Id: I1d7505cde85fed97d71b6455d5ab6401e60d6da4
Fixed package structure in the import statement of test file.

Change-Id: Id6e3e7a391487f173f2e2e630be19e7f26ac47ec