Rename http2 module m4 file, so that it will

come after most standard modules in configure
and thus will also be added later with
LoadModule to the default Unix httpd.conf file.

This is necessary, because modules/http2 also
contains mod_proxy_http2, which must be loaded
after mod_proxy itself.

The same trick is already in used for some other
modules (see config5.m4 files).


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1730071 13f79535-47bb-0310-9956-ffa450edef68