Normally, we don't have wait for child process to exit, since init can
take care of them.  But in containerized environment, pid 0 init might
not be available, and defunct processes can be piled up.  This commit
ensures that OCSP and neverbleed processes are waited for before
worker process exits.

Strict http framing

We now treat Content-Length or Transfer-Encoding as error if they come
with 204 or 1xx status code, or 200 to a CONNECT request in HTTP/1
response.