chore(development setup): setup grunt and bower for development environment

Setup angularFire-seed development environment in line with AngularFire-seed (modified to work with angularFire-seed file structure):
- create /Gruntfile.js
- create /package.json
- create /bower.json
- create /.bowerrc
- create /karma.conf.js at root
- create /.jshintrc
- create /test/.jshintrc
- install /node_modules (via node install)
- install /app/bower_components (via bower install)
- update /test/unit/configSpec.js to accept urls including numbers

Deprecates node /scripts and /config directories for serving and testing - instead use 'grunt serve' and 'grunt test'