Vault End-Point Get/Head Update

- Bug Fix: Metadata doesn't need the auth token
- Bug Fix: Sqlite didn't properly return the value
- Bug Fix: Cassandra might not properly return the value (passes tox)
- Bug Fix: bad variable names
- Bug Fix: Remove duplicate line from merge with master
-- 'file' instead of 'files' when gettings stats for disk storage driver
-- 'container_metadta' instead of 'container_metadata' when getting stats for swift storage driver
- Enhancement: Update Swift Mocking to contain required headers for container_head functionality
- Enhancement: Added test for storage driver statistics
- Enhancement: Unified the statistics tests between the storage and metadata testing
-- Renamed 'test_vault_crud' function to 'test_vault_statistics' in test_sqlite_storage_driver.py
-- Renamed 'stats' variable to 'statistics' in the test_sqlite_storage_driver.py
Vault End-Point Get/Head Update

- Fixes for pep8 complaince
-- indentations
-- lines too long