Improve Pan language support (#3691)

* Add a larger set of sample files for Pan

This is a fairly good cross section of Pan based on code from:
* https://github.com/quattor/template-library-examples
* https://github.com/quattor/template-library-core

* Add Pan language grammar

samples/Pan/purge_fqan_accounts.pan

@@ -0,0 +1,30 @@
+# Template installing a script to remove all accounts with 'fqan' in
+# their name. Used after fixing VOConfigTask in SCDB 2.3.2 to remove
+# obsolete accounts not removed by ncm-accounts.
+#
+# The script is added and executed only on nodes where NODE_VO_ACCOUNTS
+# is true. It is intended to be run as GLITE_BASE_CONFIG_SITE (define
+# this variable to the script namespace).
+#
+# Michel Jouvin - 13/9/09
+
+unique template site/misc/purge_fqan_accounts;
+
+variable LAL_PURGE_ACCOUNTS_SCRIPT = '/tmp/purge_fqan_accounts';
+
+include 'components/filecopy/config';
+
+'/software/components/filecopy/services' = {
+    if ( is_defined(NODE_VO_ACCOUNTS) && NODE_VO_ACCOUNTS ) {
+        debug('Adding purge_fqan_accounts');
+        SELF[escape(LAL_PURGE_ACCOUNTS_SCRIPT)] = dict(
+            'config', file_contents('site/misc/purge_fqan_accounts.sh'),
+            'owner', 'root:root',
+            'perms', '0755',
+            'restart', LAL_PURGE_ACCOUNTS_SCRIPT,
+        );
+    } else {
+        debug(format('VO accounts disabled (NODE_VO_ACCOUNTS=%s', NODE_VO_ACCOUNTS));
+    };
+    SELF;
+};