For HTTP/2, we do this validation in libnghttp2. http-parser does
this partially, when it parses URI, but it does not do anything for
Host header field. libspdylay does not perform anything. So do some
additional validation for HTTP/1 and SPDY cases. integration tests
were also added to make sure they work.
This commit changes nghttpx's mruby script handling. Previously we
have 2 options to specify the mruby script file to be run on request
and on response. Now they are merged into 1 option, namely
--mruby-file. It now must return object. On request, the object's
on_req(env) method is invoked with env object. Similarly, on
response, the object's on_resp(env) method is invoked. The
specification of Env object has not changed.