WebWorker-based channels

[gmhwxi]

For the purpose of teaching,
I implemented simple bi-directional communication channels based on WebWorkers:

Here is an application:

https://github.com/githwxi/ATS-Postiats-contrib/tree/master/contrib/libatscc/libatscc2js/TEST/Worker

Here is the channel implementation:

https://github.com/githwxi/ATS-Postiats-contrib/blob/master/contrib/libatscc/libatscc2js/DATS/Worker/channel.dats

Right now, the channels are untyped. It should be straightforward to support typed channels via session types.

You have to try this: It is a lot of fun :)

Cheers!