Removing projects field from component view and filtering the activities...

... and milestones by project when creating task from component view + bugfix

* When creating task from a project, project field should not show and the activities, milestones should be filtered list for that project.
* bugfix in change_password
Since the crud_form is initialised in the modules and we want to add an element in the controller, the correct way of doing it is having a adder method in S3SQLCustomForm, right? We would not want to manipulate the internals of crud_form outside it's class. Is this correct?