Merge r1703417, r1703642 from trunk:

Add in finding LUA installed via Macports and others


accept both 5.1 and 5.2, so make messages clear

Reviewed/backported by: jim


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1703650 13f79535-47bb-0310-9956-ffa450edef68