update readme
change_column_null is implemented on connection adapters -> use standard change column form
Merge pull request #180 from kevmoo/patch-1

change_column_null is implemented on connection adapters
Call downcase_keys and strip_whitespace before creating a user since they won't be triggered as before_validations.
Merge pull request #181 from rywall/patch-1

Fix issue when used with devise case_insensitive_keys and strip_whitespace_keys
upgrade to Bundler 1.1.0
add tests to support pull request #181
invite! should downcase_keys and strip_whitespace
Merge pull request #182 from unreal/master

Add tests to support pull request 181
The migration example should include the column type :string. If not we will get nasty ```undefined method `to_sym' for {:null=>true}:Hash```
allowed normal sign_up for invited users
removed the overwriting create action of RegistrationsController and implemented the according logic with an around_filter instead
Ensure the index is unique.
Merge pull request #184 from harrikauhanen/patch-1

The migration example should include the column type :string
Merge pull request #186 from bareich/issue-23

Allow normal sign_up even for invited users (issue #23)
Merge pull request #189 from cmeiklejohn/readme_unique_index

Ensure the index is unique.
ruby1.8 support
refactoring and independence from user
increased devise dependency
travis support
Merge pull request #193 from aderyabin/master

Fix a lot of bugs. It should works now