Replace build system with a faster new one that uses Node and UglifyJS and generates smaller minified files. Also removes builds through rake/ant since having 3 different build systems was too much to maintain (make was the only one consistently kept up-to-date). Fixes #7973.
Switched from using YUI Compressor to Google Compiler. Minified and Gzipped filesize reduced to 22,839 bytes from 26,169 bytes (13% decrease in filesize). Sizzle copyright was merged into the main header (since it's removed automatically). Still passes all unit tests.
Cleaned out the build directory - a lot of old files that weren't being used anymore.