FreeSWITCH performance tweaks

I have a few ideas for methods by which to improve the performance of our FreeSWITCH implementation. I'll be trying them out here. I'd love if people could test and let me know if they see any improvements in performance, and preferably which commits here make the biggest improvement (you can git bisect to find out: http://mojolingo.com/blog/2013/using-git-bisect-to-troubleshoot-ruby-gems/). Please watch this PR for changes and test regularly, letting me know if and when you see an improvement.

This stuff won't be merged until it results in reasonable performance improvements. Some of these things may also be applicable to Asterisk, and if they work for FreeSWITCH may be copied across.