Common reorg (#8025)

* Re-organize common folder

* fix: Correct paths in tests

* fix: move new content to proper folder

* chore: Move audio folder to assets

* Move sprites to sprites assets directory

* Move css sprites to assets directory

* Split out readmes for common code and sprites

* Move images to assets directory

* Move destinatin of shared browserified file

* remove unused file

* move compiled js to client-old

* Fix karma tests

* fix: Correct paths for sprites

website/common/script/libs/pickDeep.js

@@ -0,0 +1,13 @@
+// An utility to pick deep properties from an object.
+// Works like _.pick but supports nested props (ie pickDeep(obj, ['deep.property']))
+
+import _ from 'lodash';
+
+module.exports = function pickDeep (obj, properties) {
+  if (!_.isArray(properties)) throw new Error('"properties" must be an array');
+
+  let result = {};
+  _.each(properties, (prop) => _.set(result, prop, _.get(obj, prop)));
+
+  return result;
+};