Move to grunt for building all distribution files.

* canonical version number of jasmine-core is now is package.json
* `grunt buildDistribution` builds jasmine.js, jasmine-html.js, jasmine.css and outputs them to the dist dir
* `grunt buildStandaloneDist` builds the example spec runner files and compresses them to dist/jasmine-VERSION.zip
* `grunt compass` compiles jasmine.css
* jasmine.Env handling of version is backwards compatible, but uses the version string directly (and nicely deprecated)
* Ruby/thor tasks that did the above deleted

grunt/config/jshint.js

@@ -0,0 +1,17 @@
+module.exports = {
+  beforeConcat: ['src/**/*.js'],
+  afterConcat: [
+    'lib/jasmine-core/jasmine-html.js',
+    'lib/jasmine-core/jasmine.js'
+  ],
+  options: {
+    /* While it's possible that we could be considering unwanted prototype methods, mostly
+     * we're doing this because the objects are being used as maps.
+     */
+    forin: false,
+
+    /* We're fine with functions defined inside loops (setTimeout functions, etc) */
+    loopfunc: true
+  },
+  all: ['src/**/*.js']
+};