Adjust categories for some mail-related plugins

plugins/mail/imap_bandwidth

@@ -116,7 +116,7 @@ fi
 if [ "$1" = "config" ]; then
 	echo 'graph_title IMAP bandwidth'
 	echo 'graph_vlabel to (+) / from (-) server [bit/s]'
-	echo 'graph_category network'
+	echo 'graph_category mail'
 	for item in $SERVERS; do
 		key="$(echo "$item" | cut -f 1 -d =)"
 		clean_name="$(clean_fieldname "$key")"

plugins/mail/mail_connections

@@ -31,7 +31,7 @@ if [ "$1" = "config" ]; then
 graph_title Open mail server connections
 graph_args --base 1000 -l 0 
 graph_vlabel connections per second
-graph_category Mail
+graph_category mail
 EOT
 	echo "$PORTS" | while read port field label; do
 		echo "${field}.label $label"

plugins/mail/postfwd-rbl

@@ -28,7 +28,7 @@ fi
 if [ "$1" = "config" ]; then
 
         echo 'graph_title Postfwd'
-        echo 'graph_category fw'
+        echo 'graph_category spamfilter'
         echo 'graph_args --base 1000 -l 0'
         echo 'graph_vlabel Postfwd statistics'
         echo 'spamhaus.label Listed on Spamhaus.org'

plugins/mail/procmail_

@@ -35,7 +35,7 @@ sub config {
 
     print "graph_title Destination folders for Postfix\n",
     "graph_vlabel Received mails\n",
-    "graph_category Mail\n",
+    "graph_category mail\n",
     "graph_info Gives you the total mails stored by Postfix by folder\n";
     print "$_.label $_\n" foreach sort keys %{$state->{folders}};
 }