Refactor handling of rsyslog $ModLoad directives.

Break out management of $ModLoad directives in rsyslog.conf from the
syslog-service__::centos class into a new defintion rsyslog::modload,
and call that from syslog-service__::centos.

This was originally commit 36c5a0013388 in intserv.

manifests/init.pp

@@ -10,6 +10,45 @@ class syslog::vars
 }
 
 
+/*
+ * Add or remove $ModLoad directives from the rsyslog configuration.
+ */
+define rsyslog::modload($ensure='present')
+{
+    $modload_re = sprintf(
+	'^\$[Mm][Oo][Dd][Ll][Oo][Aa][Dd]\s+%s(\s*#.*)?$', $name
+    )
+
+    case $ensure
+    {
+	'present': {
+	    ensure_line {
+		"rsyslog::modload::${name}":
+		    file => '/etc/rsyslog.conf',
+		    line => "\$ModLoad ${name}",
+		    sufficient => $modload_re,
+		    addhow => prepend,
+		    require => Package['rsyslog'],
+		    notify => Service['rsyslog'];
+	    }
+	}
+	'absent': {
+	    delete_lines {
+		"rsyslog::modload::${name}":
+		    file => '/etc/rsyslog.conf',
+		    pattern => $modload_re,
+		    require => Package['rsyslog'],
+		    notify => Service['rsyslog'];
+	    }
+	}
+	default: {
+	    fail("Rsyslog::Modload[${title}]:",
+	         " Bad parameter ensure, \"${ensure}\"")
+	}
+    }
+}
+
+
 class syslog-service__::centos
 {
     package {
@@ -17,21 +56,9 @@ class syslog-service__::centos
 	    ensure => installed,
 	    notify => Service['rsyslog'];
     }
-    ensure_line {
-	syslog-get-kernel-messages:
-	    file => '/etc/rsyslog.conf',
-	    line => '$ModLoad imklog',
-	    pattern => '^\$[Mm][Oo][Dd][Ll][Oo][Aa][Dd] +imklog *$',
-	    addhow => prepend,
-	    require => Package['rsyslog'],
-	    notify => Service['rsyslog'];
-	syslog-get-local-messages:
-	    file => '/etc/rsyslog.conf',
-	    line => '$ModLoad imuxsock',
-	    pattern => '^\$[Mm][Oo][Dd][Ll][Oo][Aa][Dd] +imuxsock *$',
-	    addhow => prepend,
-	    require => Package['rsyslog'],
-	    notify => Service['rsyslog'];
+    rsyslog::modload {
+	'imklog':     ensure => present;
+	'imuxsock':   ensure => present;
     }
     service {
 	'rsyslog':