Process definition are always deployed atm.
The patch allows to set deployement to:
always (a process definition will always be deployed even if it already exists in the db at startup time, this is the default)
never (never deployed, would be the responsability of the code to do so)
ifNotExists (if a processDefinition of the same name already exists in the database, do nothing, otherwise deploy).
I added a separate folder for test (I'll start a thread in the forum about it).