Echo JS 0.11.0

SWC are planning their own type checker for TypeScript. I don't have the link to hand but if you google it, you're sure to find it.

Of course the problem with type checking is that, unlike transipiling say, you can't do it incrementally. If a TypeScript file is altered then you need to look at the effect that has on all of its dependents. If you don't want to solve this problem then you have no option but to simply rebuild the whole lot. This is at the root of why type checkers are slow. 

However, a type checker written in Rust will speed things up by at least a factor of ten and maybe many times more.