Jco transpile: implementation of wasi-http for Web

[pchickey]

Targets ServiceWorker, Fetch.

Tasks

• [ ] incoming-handler.handle
• [ ] outgoing-handler.handle
• [ ] types.drop-fields
• [ ] types.new-fields
• [ ] types.fields-get
• [ ] types.fields-set
• [ ] types.fields-delete
• [ ] types.fields-append
• [ ] types.fields-entries
• [ ] types.fields-clone
• [ ] types.finish-incoming-stream
• [ ] types.finish-outgoing-stream
• [ ] types.drop-incoming-request
• [ ] types.drop-outgoing-request
• [ ] types.incoming-request-method
• [ ] types.incoming-request-path-with-query
• [ ] types.incoming-request-scheme
• [ ] types.incoming-request-authority
• [ ] types.incoming-request-headers
• [ ] types.incoming-request-consume
• [ ] types.new-outgoing-request
• [ ] types.outgoing-request-write
• [ ] types.drop-response-outparam
• [ ] types.set-response-outparam
• [ ] types.drop-incoming-response
• [ ] types.incoming-response-status
• [ ] types.incoming-response-headers
• [ ] types.incoming-response-consume
• [ ] types.drop-outgoing-response
• [ ] types.new-outgoing-response
• [ ] types.outgoing-response-write
• [ ] types.future-incoming-response-get
• [ ] types.drop-future-incoming-response
• [ ] types.listen-to-future-incoming-response