Convert brigade to use a single key pair for config

Also general refactor,
Give tests some love

Actually make the tests work
Make stuff more modular and testable
Use Put Copy for copying files
Screw fileworkers, this is webscale
Keep track of the size of files copied
Improve stats
The world is not ready for having every file worker in its own goroutine
Use builtin AWS regions
Increase the max number of files to fetch at once
O(N) directory traversal instead of O(N^2)