Convert double quotes to single quotes in bots

Since we don't need string interpolation here, and we aren't using any
single quotes in these strings that would require escaping, we may as
well use single quotes everywhere.

At the same time, I added a trailing comma to the end of the hash.
Expand list of bots

At Causes, we have been running a user agent string check for bots with
a list I curated from our server logs. This commit adds some bots from
our list to the bots in this gem to provide a more complete and accurate
view of who is a bot.
Merge branch 'bots' of https://github.com/lencioni/browser into lencioni-bots

Extract bots to a configuration file.

Conflicts:
	lib/browser/methods/bots.rb