Add text filter
Merge pull request #130 from sexnothing/master

System module front-end code update
Changed avatar sizes: https://github.com/pi-engine/pi/wiki/Design.Avatar
Update Filter.php
Merge pull request #128 from voltan/develop

Add text filter
Updated changelog
Use grunt jsbeautifier and jshint handler js files, all js files will be
checked by this tow tools, before submit it, all js files will be not
throw error