update for devise 3.1
update gemfile lock for devise 3.1
update gemfile lock for devise 3.1
add invitation_created_at, closes #301

Conflicts:
	lib/devise_invitable/model.rb
stop testing with ruby 1.8, devise 3.1 doesn't support it
change version
remove limit from token, fixes  #351
travis_retry on bundle install
add license to gemspec, closes #353
remove unused method
test against rc2
Added missing :invitation_created_at in the down migration.
make deliver_invitation public
Extract resource invitation into its own method

This makes it possible for a subclass to override how the resource is
created (e.g. by passing a block to resource.invite!) without needing to
override the entire create method.
document new column in CHANGELOG, closes #356
Merge pull request #364 from zoras/hash_async

It should not allow user with same email to persist
Conflicts:
	Gemfile.lock
add changelog
Bump to 1.2.2 Merge branch 'devise-3.1'

Conflicts:
	Gemfile.lock
	devise_invitable.gemspec
	lib/devise_invitable/model.rb
	lib/devise_invitable/version.rb