API calls throw AWS compatible exception

Fixes bug 1271529
Merge pull request #92 from ikhudoshyn/bug/1271529

API 'create_table' call throws AWS compatible exception
Added strong consistency for items reading in tempest tests.
Merge pull request #5 from Mirantis/master

Merge with upstream
Merge pull request #93 from yyekovenko/master

Added strong consistency for items reading in tempest tests.
Check for table existence before create

Fixes bug 1271529
Merge pull request #94 from ikhudoshyn/bug/1271529

Check for table existence before create
Added verification of error message to assertBotoError mechanizm.
Removed unnecessary comment.
Catch driver specific 'AlreadyExists' exception on table create
Merge pull request #95 from ikhudoshyn/process-driver-exception-on-table-create

Catch driver specific 'AlreadyExists' exception on table create
unit tests are fixed, pep8 rules are satisfied
Merge pull request #96 from dukhlov/master

unit tests are fixed, pep8 rules are satisfied
global environment initialisation is refactored
Merge branch 'master' of https://github.com/Mirantis/magnetodb
Merge pull request #6 from Mirantis/master

Merge with upstream
unit tests are fixed, pep8 rules are satisfied
Merge pull request #99 from dukhlov/master

unit tests are fixed
Merge pull request #98 from yyekovenko/master

Added verification of error message to assertBotoError mechanizm.