First pass at cleaning up htpasswd. This removes the tmpnam call in

favor of apr_file_mktemp.  This also APR-izes most of the code.  The
file access code is still not using APR, but that will be fixed next.

I also re-organized some of the code to make it a little cleaner, and
to use functions where I could.

PR:	7764


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@95712 13f79535-47bb-0310-9956-ffa450edef68