[gnome-system-monitor] Move XML declaration to the first line in the appdata file

[Piotr Drąg <piotrdrag src gnome org>]

commit f4022e0098a9da28b3cddf8cd55d59c788171971
Author: Piotr Drąg <piotrdrag gmail com>
Date:   Fri Aug 12 00:07:26 2016 +0200

    Move XML declaration to the first line in the appdata file
    
    Otherwise, it doesn't validate and xgettext throws an error:
    
    XML or text declaration not at start of entity at line 2, column 0, byte 36 at 
/usr/lib/perl5/XML/Parser.pm line 187
    xgettext: error while opening "../gnome-system-monitor.appdata.xml.in.h" for reading: No such file or 
directory
    ERROR: xgettext failed to generate PO template file. Please consult
           error message above if there is any.

 gnome-system-monitor.appdata.xml.in |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/gnome-system-monitor.appdata.xml.in b/gnome-system-monitor.appdata.xml.in
index 1eedd05..c279107 100644
--- a/gnome-system-monitor.appdata.xml.in
+++ b/gnome-system-monitor.appdata.xml.in
@@ -1,5 +1,5 @@
-<!-- Copyright 2016 Robert Roth -->
 <?xml version="1.0" encoding="UTF-8"?>
+<!-- Copyright 2016 Robert Roth -->
 <component type="desktop">
   <id>gnome-system-monitor.desktop</id>
   <metadata_license>CC0-1.0</metadata_license>