doctrine/common — pull request #335 by jdeniau (2014-08-28 16:02:23+00:00)
Title: add base events class

Hi,

All doctrine projects implements events. A lot of them are similars, but there is no base class defining common Events.

I tried to gathen them all in this PR. I looked into ```CouchDb-orm```, ```doctrine-orm```, ```doctrine-mongodb-odm``` and ```phpcr-odm```.

I only added events present in all packages, but CouchDB is the only one to not implement some events implemented in every other packages (```postPersist```, ```loadClassmetadata```, ```preFlush```, etc.).