Night mode CSS for multireddits beta
More night mode tweaks

Search form text/visited links against focused background
CSS fix for tumblr text expandos

Related to a5bb5ae0fadd7c1e121d11fd15b79620d32d02a4
Preliminary 'Troubleshooting' module

Making it easier for users to trim tags and refresh cached
user/subreddit info.
Merge pull request #444 from gavin19/master

Night mode CSS for multireddits beta