* Add full implemention of Map and Set to shims
* Update default Map interface
* Remove WeakMap/WeakSet
* Add tests for set shim
* Update most usages of Map<K, true> to Set
* PR Feedback
* Fix lint issues
* Change key in fsWatchCallback
* Simpler shim, more tests
* Fix typo in collection shim
* Move most harness globals into namespaces
* Remove forward declaration from `createMapShim` and move all `Map` declarations into one file
* A small pile of more changes to get the harness transforming