TypeScript globals & Module class

[chharvey]

Second PR as part of #8826. This PR adds global functions, accessible from the binaryen namespace. Also sets up the Module class and some instance methods.

import * as binaryen from "binaryen.ts";
binaryen.getExpressionType(your_expr);
const mod = new binaryen.Module();
mod.validate();

This PR is stacked on #8861 (i.e. it depends on that being merged first. the diff will be easier to compare once that happens, or you can compare here).

Adds 1 deprecation: the global function getSideEffects() is deprecated in favor of the instance method Module#getSideEffects(). The global function is still supported but it will log a warning to console:

"Global function getSideEffects(expr, mod) is deprecated; use mod.getSideEffects(expr) instead."

Some global functions are still commented out as they depend on Expression classes: the Expression() function (called without new), returns a class instance containing information about a wasm expression, and the getExpressionInfo function, which similarly returns a JSON object. Internally they depend on an EXPRESSION_TYPE_REGISTRY map. These will be uncommented once the Expression class & subclasses are added in a future PR (for a preview, see #8826).