1.1.3dev: Remove trailing whitespace from option doc strings. Refs #11824.

`cleandoc` in `trac.util` removes leading and trailing whitespace from messages.


git-svn-id: http://trac.edgewall.org/intertrac/log:/trunk@13311 af82e41b-90c4-0310-8c96-b1721e28e2e2