Implemented Text API which updates id_map and ast on each code change.
This PR contains also an implementation for actual opening and initializing Module Controller.
Added a "Text changed" callback to TextField which is fired on every user edit.
Original commit: b027517b34
This PR brings code necessary to fully integrate file manager and properly use it.
Two most important parts are:
* executor that can be integrated with basegl's event loop;
* implementation of the `Transport` trait based on `web_sys::WebSocket`.
I've also added some glue code to put the file manager connection into the project view.
Implements #2105.
Original commit: 64c06632e1
This contains an initial TextController implementation, which can read and store the file content, and is obtainable from ProjectController.
Original commit: 66f4dfd0fa
