Add support for EL8 systems.

The packaging of fetch-crl in EPEL-8 uses a systemd timer unit,
instead of a cron job, to run fetch-crl regularly.  Thus, in EL-8
we need to manage the 'fetch-crl.timer' service instead of the old
'fetch-crl-cron' and 'fetch-crl-boot' services.

Signed-off-by: Thomas Bellman <bellman@nsc.liu.se>

manifests/fetchcrl.pp

@@ -20,7 +20,7 @@ class x509certs::fetchcrl
 		    notify => Exec['x509certs::fetchcrl::initial'];
 	    }
 	}
-	/^(CentOS|RedHat|Scientific):(7)(\.[^:]+)?$/: {
+	/^(CentOS|RedHat|Scientific):([7-8])(\.[^:]+)?$/: {
 	    package {
 		'perl-LWP-Protocol-https':
 		    ensure => installed, before => Package['fetch-crl'],
@@ -40,14 +40,32 @@ class x509certs::fetchcrl
 	    # Obsolete; now just an empty package depending on fetch-crl.
 	    ensure => absent;
     }
-    service {
-	'fetch-crl-cron':
-	    enable => true, ensure => running,
-	    require => Package['fetch-crl'];
-	'fetch-crl-boot':
-	    enable => false,
-	    require => Package['fetch-crl'];
+
+    # Activate services as required per operatingsystem
+    case "${::operatingsystem}:${::operatingsystemrelease}"
+    {
+	/^(CentOS|RedHat|Scientific):([6-7])(\.[^:]+)?$/: {
+	    service {
+		'fetch-crl-cron':
+		    enable => true, ensure => running,
+		    require => Package['fetch-crl'];
+		'fetch-crl-boot':
+		    enable => false,
+		    require => Package['fetch-crl'];
+	    }
+	}
+	/^(CentOS|RedHat|Scientific):(8)(\.[^:]+)?$/: {
+	    service {
+		'fetch-crl.timer':
+		    enable => true, ensure => running,
+		    require => Package['fetch-crl'];
+	    }
+	}
+	default: {
+	    fail("X509certs::Fetchcrl: Unsupported operating system")
+	}
     }
+
     exec {
 	'x509certs::fetchcrl::initial':
 	    command => '/usr/sbin/fetch-crl -p 16',