What to do about plugins?

[goanpeca]

3rd Party Plugins
Installing these plugins will add extra functionality to the language server:

pyls-mypy Mypy type checking for Python 3
pyls-isort Isort import sort code formatting
pyls-black for code formatting using Black

[ccordoba12]

We can add some of them as new dependencies here (e.g. Mypy integration was required by Universidad de los Andes and black integration would be really cool too).

But let's leave that to do it after beta2.