Merge branch 'release/5.0.0.alpha4' into develop

* release/5.0.0.alpha4:
  * Reformatted changelog
* Support for mongoid 4.0.0.alpha2
* Fixed readme
Merge branch 'release/5.0.0.alpha5'

* release/5.0.0.alpha5:
  * Support for mongoid 4.0.0.alpha2 * Fixed readme