Bump to 3.1.0
Fix typo in README
Require Paperclip::Schema only when used with AR

This will solve an issue when using Paperclip without Active Record
such as Mongoid.

Fixes #919
Bump to 3.1.1
Pass only column name to `#remove_column`

@mvz caught this in 90ea9dab5b81b3cf5ba91d34ab6ffb4b4c6d8af8.
Thank you!
Bump to 3.1.2

Also, 3.1.0 and 3.1.1 will be yanked because of the regression.
Adds a class for managing content type detection
Extra checking on the content type detector
Bringing back functionality to allow StringioAdapter to accept content_type and original_filename
Gracefully handle a missing file command
Make command line error handling more generic
Added support for created_at field
Stick fog to 1.3.1
Update migration generation instruction
Quick Start fixes for Rail 3.2.3 compat
Add Code Climate badge
Update Paperclip's default URL in documentation
Update default path documentation

Now it includes :class and :id_partition
Remove whitespace, fix code styling
[#940] Raise error when style defined & not in path

* Add StyleTokenNotFound in Errors
* Adjust tests to make sure :style present where not currently defined