Merge branch 'master' of https://github.com/mongoid/mongoid into master-issues
Fixes touch frozen docs [ #2779 ]

When trying to touch a document that is frozen(delete , for instance), write_attribute cannot happen.
Update changelog
Revert "Fixes touch frozen docs [ #2779 ]"

This reverts commit b45a4aa17327b8870928f2e211fcd8e505605cd1.
Update changelog
Fix broken DateTime conversions.

[ fix #2781 ]
[ fix #2777 ]
Fix broken spec
fix time with zone spec
add license information to gemspec

This way it can be used with the rubygems.org API
switch the class to create criteria for uniqueness validation when the field is defined in ancestor class.
[ fix #2783 ]
Update changelog, implementation
Fix regression on destroy callbacks not cascading.

[ fix #2786 ]
Fix changelog
Bump moped dependency to 1.4.0
Theoretically adding max_scan support once https://github.com/mongoid/moped/pull/144 or similar is accepted.
Update changelog
Memoize atomic path
Merge branch 'master' of https://github.com/mongoid/mongoid into master-issues
Don't autobuild on reading for validation.

[ fix #2794 ]
Ensure becomes replaces instances in the identity map.

[ fix #2787 ]