Improve test coverage of web-based administrative tools.
Improve test coverage of web-based administrative tools.

Author: glyph

Reviewer: exarkun

Fixes #2129

This change adds coverage specifically for the scrolltable actions which invoke
the forms to endow, deprive, suspend, and unsuspend.  It also corrects a few
coding-standard compliance issues in the tests.

twisted/mantissa,twisted/mantissa,twisted/mantissa