Detect which version of the chat we are using

The new chat filter doesn't work for the old chat. Ideally we would have
one single filter for both, but for now we are going to have to live
with this hacky solution.

We have to test for the new chat filter with a DOM element, and I don't
have the new chat, so I picked button.viewers. Not sure if that is the
best choice but that's one of the few unique things I see in the new
filter.
Fix bug in greasemonkey

Thanks to @hugomg
Merge pull request #73 from ajhodges/master

Detect which version of the chat we are using
Increment userscript version no. to 1.8
Fix feature detection for greasemonkey

Greasemonkey was incorrectly treating new chat users as old chat users,
causing it to get stuck in the "loading" forever. This is because we were
trying to use DOM operations for feature detection before the DOM was ready.
Add beta.twitch.tv to userscript header

beta.twitch.tv can be used to test the new chat!
Merge pull request #75 from hugomg/feature-detect

Fix feature detection for greasemonkey
Stop waiting for the chat spinner

Now that we are overriding the Chat prototype instead of the chat objects
themselves we can get rid of the chat spinner wait. This makes the script
seem more responsive and also simplifies the code a bit (one less thing to
worry about when it comes to new chat compatibility)

The chat_is_loaded variables was kind of pointless too. We can't click on
any of the configuration buttons before the loading spinner goes away.
Merge pull request #77 from hugomg/initialize

Stop waiting for the chat spinner
Better styling for updated Twitch chat.