Convert adapters to TypeScript

[benmccann]

It looks like adapter-begin, adapter-static, and adapter-vercel are in .js

adapter-netlify and adapter-node are in .ts so are examples that could be looked at when converting

[benmccann]

Need to do adapter-begin still.

And also https://github.com/sveltejs/kit/blob/master/packages/adapter-netlify/index.js which is blocked by a new release of tiny-glob which includes terkelg/tiny-glob#54

I'll send a PR for two other remaining files:

• https://github.com/sveltejs/kit/blob/master/packages/adapter-node/index.js
• https://github.com/sveltejs/kit/blob/master/packages/adapter-vercel/index.js

[benmccann]

Closing. Only one left to do is the Begin adapter. I filed #175 to track that