* Add typescript as a valid parser value
Now that typescript development has started, each contributor has been adding this as a supported flag themselves.
This just adds it as an allowed option, with a warning that support for this parser is experimental.
I also tried to structure this a bit future proof, in case other experimental parsers come along.
* Simplifies the code at vjeux's request
Rather than a notion of "experimental" parsers, we'll just leave typescript out of the documentation until it's supported.
Pi Lanningham
5e7503dadd