Formatting fix (removed blank lines)
Minor fixes for Attributes#check!

* Removed code duplication
* Fixed formatting (blank lines)
* Fixed handling for attrs not in definitions
Merge pull request #62 from arax/attr_fix

Minor fixes for Attributes#check!
Minor updates in logging and exceptions

* Wrapped long lines
* Including key names in exceptions thrown after a type mismatch
* Minor logging fixes
Added class name to a log message
Merge pull request #63 from arax/attr_fix

Minor updates in logging and exceptions
Updated Docs
Version bump to 4.2.0
Merge pull request #64 from arax/release_42

Staging for the 4.2.0 release
Fixed attribute validation for attrs w deep diff
Minor version bump to 4.2.1
Bunch of minor bugfixes

* Updated locations for links and mixins
* Updated JSON rendering for mixins (depends)
* Updated specs (new locations)
Merge pull request #65 from arax/mixin_fix

Bunch of minor bugfixes
Fixed property handling for attributes
Merge pull request #66 from arax/prop_fix

Fixed property handling for attributes
Fixed properties for deep hashes
Minor version bump to 4.2.2
Fixed link rendering to text/plain
Fixed text/plain parsing of rel="..."
Fixed related_to? for mixins