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/fns/dotSet.js

@@ -0,0 +1,14 @@
+import _ from 'lodash';
+
+/*
+ This allows you to set object properties by dot-path. Eg, you can run pathSet('stats.hp',50,user) which is the same as
+ user.stats.hp = 50. This is useful because in our habitrpg-shared functions we're returning changesets as {path:value},
+ so that different consumers can implement setters their own way. Derby needs model.set(path, value) for example, where
+ Angular sets object properties directly - in which case, this function will be used.
+*/
+
+// TODO use directly _.set and remove this fn, only used in client
+
+module.exports = function dotSet (user, path, val) {
+  return _.set(user, path, val);
+};