Emit events on every major action

The Readme file promises, that there are events thrown on every major action of a CRUD operation, but unfortunately the [LiipEventManagerModule](https://github.com/liip/LiipDrupalEventManagerModule) is not far enough evolved to handle requests other then those of the method POST.
This issue is therefore linked to the evolution of the depending module to be finished.

[Issue](https://github.com/liip/LiipDrupalEventManagerModule/issues/2) at LiipEventManagerModule.

Read the README promise about events for CRUD actions, then inspect the linked LiipEventManagerModule issue 2, which tracks the dependency's support for requests beyond POST. The work is done when that dependency evolution is finished and this module emits events for every major CRUD action.

Written by the indexing model from the issue text.