Unload communities in reversed auto load order.
Merge pull request #50 from boudewijn-tribler/code-cleanup

Bugfix: missing import.
Merge pull request #47 from boudewijn-tribler/dispersy-stop

Unload communities in reversed auto load order.
Fixes exception.

An undocumented IndexError can occur in low level inspection code, if
it does, we now assume the source file and line numer are unknown.
Merge pull request #53 from boudewijn-tribler/bugfixes

Fixes exception.