Twice as fast as acorn - impressive.

Looked at the parser code - it's well crafted. Works with integers instead of strings wherever possible.

The API is dead simple. Produces standard ESTree AST. Should take 10 minutes to port projects from `acorn` and `esprima` to `cherow`.

I wonder why he had Typescript target ES2015 only to use Buble to convert to ES5. Perhaps Buble produces more performant ES5 code than Typescript?