Parse imported variables

[privatenumber]

I believe this is a duplicate of #100. It was resolved by providing information on exported variables, but the actual request was for imports.

In my use-case, I'd like to be able to extract the variables (a & c) from a statement like this:

import/*
long comment
*/{
		a,
		b as c
}from/*
long comment
*/'file'

Additionally, I'd like to know the ranges for where the import names start and end: { a, b as c}

[guybedford]

I'm open to adding this feature, if we can try to keep the footprint overhead down.