Currently, the error 'URI incorrectly encoded' error message uses `r->uri` which may be unhelpful. For example, issuing the following command:

$ python -c 'print "GET /index.html?foo=bar\x0F HTTP/1.1\r\nHost: localhost:8080\r\n\r\n"' | nc localhost 8080

leads to the following error:

[Thu May 10 11:03:39.048134 2018] [core:debug] [pid 22836:tid 123145529880576] protocol.c(838): [client ::1:56524] AH03454: HTTP Request Line; URI incorrectly encoded: '/index.html'

whereas using `r->unparsed_uri` would show:

[Thu May 10 11:06:14.515688 2018] [core:debug] [pid 31904:tid 123145333022720] protocol.c(838): [client ::1:56533] AH03454: HTTP Request Line; URI incorrectly encoded: '/index.html?foo=bar\x0f'