Allow long daemon log messages to be expanded

Summary:
Ref T3557. We summarize long messages, but don't let you see the entire message. This is occasionally inconvenient, and I'm planning to add more prefix junk to some messages for T2569.

Provide a link you can click to see the full message.

This isn't javascripted because a ton of these can make the page ridiculously enormous and it seems unlikely you'd care much about all of them.

Test Plan: {F51261} {F51262}

Reviewers: btrahan

Reviewed By: btrahan

CC: aran, chad

Maniphest Tasks: T3557

Differential Revision: https://secure.phabricator.com/D6546