add support for digest authentication to the authn_dbm module. The

key is "$user:$realm" (perl speaking), the value is the MD5-hash,
optionally followed by a colon and other garbage.

Note that currently there's no tool to create such databases.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@98144 13f79535-47bb-0310-9956-ffa450edef68