Don't wrap task/revision titles in graph tables

Summary:
Fixes T11274. When task titles are long, we currently wrap stuff and the trace graph renders real weird.

Instead, prevent taks/revision titles from wrapping/overflowing.

(This works in a slightly weird way, and text-overflow: ellipsis; has no apparent effect on any of the containers.)

Test Plan:

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T11274

Differential Revision: https://secure.phabricator.com/D16233