Basic grid system, resizing (kind of working)
Mouse resize of elements
ab-grid: resizable elements + gutter
Fix placeholder size bug, move style into its own file
Split code into separated files, drag & drop base
Drag & drop kind of working
Grid layout: basic integration in workspace
Update polymer elements style
Fix drag & drop bug on Firefox, refactor elements CSS
Some styling & small bug fixes
Add jshintrc, edit on clic, fix bug on Node-Webkit
Merge branch 'feature/grid-layout' into develop