Add the wiki configuration template

Create a template for the wiki configuration with the db user and password
and the secret key and upgrade key

roles/archwiki/templates/LocalSettings.php.j2

+<?php
+# This file was automatically generated by the MediaWiki 1.19.0
+# installer. If you make manual changes, please keep track in case you
+# need to recreate them later.
+#
+# See includes/DefaultSettings.php for all configurable settings
+# and their default values, but don't forget to make changes in _this_
+# file, not there.
+#
+# Further documentation for configuration settings may be found at:
+# http://www.mediawiki.org/wiki/Manual:Configuration_settings
+
+# Protect against web entry
+if ( !defined( 'MEDIAWIKI' ) ) {
+	exit;
+}
+
+## Database settings
+$wgDBname = "{{ archwiki_db }}";
+$wgDBuser = "{{ archwiki_db_user }}";
+$wgDBpassword = "{{ archwiki_db_password }}";
+
+$wgSecretKey = "{{ archwiki_wg_secret_key }}";
+
+# Site upgrade key. Must be set to a string (default provided) to turn on the
+# web installer while LocalSettings.php is in place
+$wgUpgradeKey = "{{ archwiki_wg_upgrade_key }}";
+
+# Enabled Extensions. Most extensions are enabled by including the base extension file here
+# but check specific extension documentation for more details
+# The following extensions were automatically enabled:
+require_once( "$IP/extensions/FunnyQuestion/FunnyQuestion.php" );
+$wgFunnyQuestionHash = '2341Euchah1Aev6eejoo5waf';
+$wgFunnyQuestions = array();
+$wgFunnyQuestions['en']['What is the output of "pacman -V|base32|head -1"'] = "BIQC4LJNFYQCAIBAEAQCAIBAEAQCAIBAEAQCAICQMFRW2YLOEB3DKLRQFYZCALJANRUWEYLMOBWS";
+
+# End of automatically generated settings.
+
+# Add more configuration in the file included below.
+require( "LocalSettings.archlinux.org.php" );