Add comments to policy files.

appvm/qubes.Filecopy.policy

@@ -1 +1,6 @@
+## Note that policy parsing stops at the first match,
+## so adding anything below "$anyvm $anyvm action" line will have no effect
+
+## Please use a single # to start your custom comments
+
 $anyvm	$anyvm	ask,user=root

appvm/qubes.OpenInVM.policy

@@ -1,2 +1,7 @@
+## Note that policy parsing stops at the first match,
+## so adding anything below "$anyvm $anyvm action" line will have no effect
+
+## Please use a single # to start your custom comments
+
 $anyvm	$dispvm	allow
 $anyvm	$anyvm	ask

dom0/aux-tools/qubes.ReceiveUpdates.policy

@@ -1 +1,6 @@
+## Note that policy parsing stops at the first match,
+## so adding anything below "$anyvm $anyvm action" line will have no effect
+
+## Please use a single # to start your custom comments
+
 $anyvm	dom0	allow

dom0/qubes.SyncAppMenus.policy

@@ -1 +1,6 @@
+## Note that policy parsing stops at the first match,
+## so adding anything below "$anyvm $anyvm action" line will have no effect
+
+## Please use a single # to start your custom comments
+
 $anyvm	dom0	allow

qrexec/qrexec_policy

@@ -12,6 +12,10 @@ def line_to_dict(line):
     tokens=line.split()
     if len(tokens) < 3:
         return None
+
+    if tokens[0][0] == '#':
+        return None  
+
     dict={}
     dict['source']=tokens[0]
     dict['dest']=tokens[1]