v0.2: Ex Post Facto

Another two months, another new release. You can now post replies and new
threads; pretty advanced, right?

Re: development, sorry I've been slow. I've got something cool tangentially
c4-related almost ready for public release though, hopefully it'll make up
for that.

Disclaimer: If you're trying this out for the first time, remember that it's
very alpha. I think you'll still find c4 useful for a lot of 4chan browsing,
but, like, don't let your NEET lifestyle depend on it; it might let you down.

Changes:

• Reworked post date display to be very close to twitter e.g. '1h', '23m'
  instead of the verbose '23 minutes ago'. As a bonus there's now room for
  a StackOverflow-style absolute date, making c4 much more screencappable.
• Fixed some long-standing javascript errors in the console.
• Reverted removal of posting functionality, and fixed the resto post
  parameter.

Known issues:

• Something is broken with the sessionStorage-cached thread data used to
  restore state from the browser back button, causing the thread be missing
  posts until a new reply is received. Temporary fix is to clear your session
  storage or restart your browser.
• Hovering over GIFS in Firefox 26 will ocassionally freeze the browser from
  10-30 seconds. I have a hard time isolating this one, but I think it might
  be an firefox extension issue I have since I've been able to reproduce it with
  4chanX's image hover too. If anybody comes across this issue, please report
  it to https://github.com/qqueue/c4/issues and list your extensions.