Add optimistic locking support automatically for tables with a lock_version
Add documentation
Include lock_version support for update! and update operations
Fixed two comments that were transposed
Merge pull request #118 from loganb/optimistic_locking

Add optimistic locking support automatically for tables with a lock_version
Use QUERY when WHERE clause has HASH KEY.
Use a range query when only a hash key or range key is specified in query. Includes tests.
Update .gitignore for RubyMine.
Merge pull request #122 from stefanneculai/where_by_key

Fix for issue #120