[#167] upgraded to grunt 0.4 and fixed the build system

Currently broken (todo) :
* jshint : generates too much error and is not part for now of the
default build option (source code need lots of fixes first)
* coffeescript : requires a new .coffeescript file (can anyone help?)
* banner: removed from now as format changed with grunt 0.4
* jsdoc; to be added (together with a new template for version 3.x)