README: typo fix on attributes
Fix rails 4.0.x build
Dont allow failures on 4.0.x
Add .ruby-version to gitignore
Rails does not support const_defined? in development mode;
Use const_get instead, and rescue NameError
Merge pull request #614 from arthurnn/fix_build_40

Fix rails 4.0.x build.
Merge pull request #613 from spk/readme_fix_attributes

README: typo fix on attributes
Merge pull request #615 from tpitale/fix-serializer-lookup

Rails does not support const_defined? in development mode
Merge remote-tracking branch 'upstream/master' into feature/adapter