Move http interface and plugin to its own repo

[krisbitney]

As part of an effort to move all the interfaces and plugins outside of the toolchain repo, I moved the http plugin and interface to their own repo here: https://github.com/polywrap/http

There is a temporary extra redirect to avoid breaking changes with wrappers that use the old package URI:

{
  from: new Uri("wrap://ens/http.polywrap.eth"),
  to: new Uri(defaultInterfaces.http),
},

[Niraj-Kamdar]

LGTM!