makefile improvements

* switch from validate to check
* jshint
* jscs
* set up media/js/src and media/js/tests to organize js better

I had to include the jshint and jscs config files as 'jshintrc' and 'jscsrc'
respectively and point at them with --config flags instead of putting them
straight at .jshintrc and .jscsrc. This is because Paste templates don't
seem to be aware of dotfiles. Couldn't really think of a cleaner way of
setting it up.