pidgin/purple-plugin-pack

Use the meson summary instead of manually building our summary with message

Testing Done:
Ran `ninja reconfigure` and verified the output.

```
purple-plugin-pack 2.8.1dev

libpurple
install directory: /usr/local/lib/purple-2
data directory : /usr/local/share
plugins : autoreply, bash, capsnot, colorize, dewysiwygification, dice, eight_ball, flip,
google, groupmsg, highlight, ignore, irc-more, irchelper, listhandler, ning,
oldlogger, omegle, showoffline, simfix, slashexec, snpp, splitter, sslinfo,
translate, xmppprio

pidgin
install directory: /usr/local/lib/pidgin
data directory : /usr/local/share
plugins : album, blistops, convbadger, difftopic, enhancedhist, gRIM, icon-override, irssi,
lastseen, listlog, mystatusbox, nicksaid, plonkers, schedule, sepandtab,
switchspell, timelog

finch
install directory: /usr/local/lib
data directory : /usr/local/share
plugins :

User defined options
backend : ninja
```

Reviewed at https://reviews.imfreedom.org/r/2408/
/*
* Purple Plugin Pack
* Copyright (C) 2003-2008
* See ../AUTHORS for a list of all authors
*
* listhandler: Provides importing, exporting, and copying functions
* for accounts' buddy lists.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301, USA.
*/
/* If you can't figure out what this line is for, DON'T TOUCH IT. */
#include "../common/pp_internal.h"
#include <string.h>
/* Purple headers */
#include <account.h>
#include <blist.h>
#include <debug.h>
#include <plugin.h>
#include <request.h>
#include <xmlnode.h>
#include "lh_util.h"
/* we send this to the request API so it is probably a good idea to make sure
* the other files that need it have it */
extern PurplePlugin *listhandler;