added javascript setup and structure
- therefore added new grunt modules:
  - grunt-contrib-uglify
  - grunt-includes
  - grunt-jsdoc
  - grunt-modernizr
- updated the Grunfile.js
- included the main.js to our html-layout-file
set generated files in folders ´svgmin´ and ´png-fallback´ to .gitignore
Merge branch 'master' of https://github.com/rastersysteme/project-kickstart-assemble