added minimize then reveal effect inspired by a codepen

the video of this effect~
http://www.youtube.com/watch?v=5ko2BkIs2wM

effect is sourced/inspired from:
http://codepen.io/matthoiland/pen/vHFCk

P.S. about the commit
1. Added Effect
2. Trailing white spaces are being deleted by sublime text.
3. Need to run "grunt" afterwards to see effect. (Only hand typed
changes are being uploaded, grunt generated files are ignored.)
4. Used Galaxy S4 to tune the performance.