1.0.3dev: Simplify code by using `separated` from `trac.util.presentation`. Refs #11689.

Removed an unused import.


git-svn-id: http://trac.edgewall.org/intertrac/log:/branches/1.0-stable@13164 af82e41b-90c4-0310-8c96-b1721e28e2e2