Added Mapper:NullMapper for testing purposes
Tests are now runnable from rspec indepentdently
Merge pull request #7 from choski7/master

Tests are now runnable from rspec independently
Allow multi_reference to specify the class name of the attribute
Gemfile.lock modified during bundle update
Cleanup comments and fix documentation comment of BaseEntity.multi_reference
Updated README with test info
Added CREDITS.txt
Readability changes and bug fix from pull-request #2 (manually cherry-picked)
Cleanup transaction after each test
Merge pull request #11 from choski7/master

Cleanup transaction after each test
Removed .empty? cjhecks before .each statements