moving the icons to mixins-helper
creating icon mixins for the app
- load icon() in the homepage
- loading facebook icon
- renaming me-home-logo-header to me-home-logo-small
-optimizng the sprite mixin
- adding icon content mixin
removing extra comments
- making sure mixin file doesn't generate any css by default
update grunt-contrib-less so it will support "replace" function.
also removing some unnecessary packages in the dependencies