Some small changes to deployment.

Removed last of Rubber configs and updated deploy/production.rb to use new server IP. These fixes were added as a hotfix to master but broke travis for some reason but now it'll be isolated into a pull request. Following this commit, all commits to master should be deployable.
Lowered number of Unicorn workers.

Bundle takes up too much memory so the number of Unicorn workers have been reduced from 5 to 3, clearing up some memory. I don't think this fixes the problem which I think lies with huge dependencies.
Merge pull request #148 from tmcyf/hotfixes-for-deploy

Some small changes to deployment