added node.js and gruntfile for javascript development
excluded node_modules in gitignore
Merge branch 'dev'

git-svn-id: https://projecthost.cs.technik.fhnw.ch/stud/ip_3bb13_puzzligenerator/svn/trunk@23 5a5f8b1a-b5cb-41ca-84ef-24cc03a2aca4