Bug fix, Task permissions(SSF)

Bug 1: http://demo.sahanafoundation.org/eden/pr/person/93/config
Bug 2: Duplicate doesn't work -- http://demo.sahanafoundation.org/eden/admin/user/1
Bug 3: I didn't handle the deleting of tasks when the task is open in SSF, my bad.
Also, allow authenticated users to create tasks in Sunflower.
Coding convention: except should always have an exception type, don't just catch everything. 

Only Exceptions which are expected should ever be caught - everything that is not expected shall crash.