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
I am confused. There are 2 problems here - 
1. Not showing the project field from task component view and filtering activities, milestones for the current project for BOTH update and create forms. (To be done by validators/filterby)
2. When not in component view, showing the project field for task (creating, updating, etc). And filter the activities, milestones when the project is changed. (To be done by S3OptionsFilter JS)

The above comment was for Problem #1 here. If filterby cannot filter the activities, milestones on create, then I think it is best to use the validators as I did before.

For Problem #2, we would have to make S3OptionsFilter JS working with whichever widget we want to use.