Add replicate as new storage feature.

This feature shows that the storage can send and receive images.

PVE/Storage/ZFSPoolPlugin.pm

@@ -700,6 +700,7 @@ sub volume_has_feature {
 	template => { current => 1},
 	copy => { base => 1, current => 1},
 	sparseinit => { base => 1, current => 1},
+	replicate => { base => 1, current => 1},
     };
 
     my ($vtype, $name, $vmid, $basename, $basevmid, $isBase) =