AssemblyScript files use .ts extensions

[trusktr]

.as isn't conventional in AssemblyScript, at least not at the moment.

There should be a way to support .ts files (which work seamlessly with TypeScript other TypeScript tooling like VS Code intellisense, Prettier, etc) without using .as extensions.

Maybe it should read a folder name or a config file or something. F.e. asconfig.json, or assembly/.