Replaced custom make with Grunt build system. Closes gh-717.
Use a custom build task in grunt to build raphael in a way that creates a valid anonymous module for AMD definition.

- Also pulls in the version from package.json to create the banner from copy.js (so the version can be set in one place)
- Conforms Gruntfile to most common tabs and spacing of other files
- grunt-cli should not be included in devDependencies (it is only ever installed globally)
Merge pull request #724 from timmywil/grunt_modules

Build Raphael as a compatible anonymous module for AMD using Grunt