Support shorthand object literals in JSHydra

[sebastian]

Background

JSHydra doesn't support the shorthand syntax for object literals, where property names are identical to the variable names they are initialized from, e.g:

let a = 1;
let b = 2;
let o = {a, b}

I found doing that quite often in functions passing multiple return values wrapped into an object.

What to change

Make JSHydra convert {a, b} into:

{a: a, b: b}

Also support mixing of explicit and implicit property inilization. So {a, b: 42}should be converted to:

{a: a, b: 42}

[sebastian]

jsHydra is no longer maintained, as we don't transpile the code anymore.