implement grunt build task using usemin, useminPrepare, cssmin, clean, copy, and, implicitly, concat and uglify.  move index.html into public/ dir rather than public/app/ so that usemin can find it with default settings, make sure .tmp/ dir is not committed to repo. concat and minification is now working correctly for js and css but we still need to run angular preprocessing steps to make sure we do not break angular during minification - either that or we need to create minsafe arrays for everywhere we inject dependencies in angular