wireproto: service multiple command requests per HTTP request Now that our new frame-based protocol server can understand how to ingest multiple, possibly interleaved, command requests, let's hook it up to the HTTP server. The code on the HTTP side of things is still a bit hacky. We need a bit of work around error handling, content types, etc. But it's a start. Among the added tests, we demonstrate that a client can send frames for multiple commands iterleaved with each other and that a later issued command can respond before the first one has finished sending. This makes our multi-request model technically superior to the previous "batch" command. Differential Revision: https://phab.mercurial-scm.org/D2871