Removed eslint from compile step

With this patch, linting becomes an entirely separate step, invoked
by 'npm run lint'. It is no longer baked into our compile, build,
package flow.

Change-Id: Ic167ce7ffdee704d9c21be6db07884bfd06a3e33

Gruntfile.js

@@ -569,7 +569,6 @@ module.exports = function (grunt) {
      * Compiles all of our sources.
      */
     grunt.registerTask('compile', [
-        'eslint',
         'useminPrepare',
         'concat',
         'less',