Clean up check_cmd_context stuff. Fix core documentation for a few

directives.

Reviewed by:	Jim Jagielski, Ken Coar, Martin Kraemer


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/1.3.x@79608 13f79535-47bb-0310-9956-ffa450edef68