Automate few /static resourses things

[wiktor-obrebski]

We need:

• auto-compile LESS files
• auto-combining and minifying css files
• auto-combining and minifying js scripts

[wiktor-obrebski]

in develop mode:

• LESS files should be compiled in watch mode, client-side
• js and css files should be included without combining and minifying - to make develop process faster

[wiktor-obrebski]

done. need docs.