Add CORSService to support CORS

[crookse]

Check the logic against expressjs/cors

[ebebbington]

it fails in browsers and via fetch because the origin header isn't set, hence why it passes in the ci

[ebebbington]

(after investigating)

[ebebbington]

Try going to deno.land and make a fetch req in the console to your server?

[ebebbington]

(My server set cors origin to google.com, i made these requests from the dev console on https://deno.land)

[crookse]

ok.. i just tested this locally and it works as expected.. idk why i ran into issues earlier... dafuq. imma write the docs for this

[crookse]

closing because of staleness. will come back to it later if needed