Add core version query function ap_get_server_revision and

accompanying ap_version_t structure (minor MMN bump).
The function is similar to apr_version() and allow for exact
querying of the core revision level.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@102405 13f79535-47bb-0310-9956-ffa450edef68