AbstractProcess.process() method should be protected

Invocations to AbstractProcess.process() will be replaced by AbstractProcess.get()

AbstractProcess.process() method body is code generated and contains the KIE process definition used by the engine. 

Every time this method is invoked, a new process definifition (which is not mutable) is generated.

To prevent that a new AbstractProcess.get() method that only initializes the process definition once was added with another JIRA.

This Jira will make process() protected and replace its usage by the get() public one.