Added missing links to htdocs/manual/mod/directives.html

for AllowCONNECT and ProxyDomain.

Submitted by: Patrik Grip-Jansson <patrikj@gnulix.org>, Ralf S. Engelschall
Reviewed by: Ralf S. Engelschall
PR: 5319


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@84171 13f79535-47bb-0310-9956-ffa450edef68