Use ActiveSupport::Concern in every mixin module
Use ActiveSupport::Concern#included rather than Module.included
Organize Mixin::ShouldBase
Organize Mixin::MonkeyPatch
Organize Mixin::MonkeyPatchAnyInstance
Organize Mixin::AllowNoMessage
Organize Mixin::AnyInstanceBlock
Refactor with Mixin::ExpectBase
Merge branch 'organize-mixins'