moving the pieces of @expand around so it's more user friendly.
moved @expand to its own repository.
good bye breeze-viz (in its own repo.)
no more doc folder (working on merging all of breeze into one
directory...)
no more benchmark... getting close!
updating readme.
moving core to math.
Breeze now lives in one project.

I'm going to break out a few more pieces from core into
their own separate libraries, but not yet.
Moved from project/Project.scala to build.sbt