Ship system_config with bundles again.

This partially reverts commit ac40945ff9.
re-add system_config, but not instant.xml

tools/linux_packaging/build

@@ -620,6 +620,7 @@ cp $BUILD_ROOT/gtk2_ardour/default_ui_config $Etc
 
 mkdir ${Shared}/icons
 mkdir ${Shared}/resources
+cp ../../system_config $Etc/system_config
 cp ../../gtk2_ardour/icons/*.png ${Shared}/icons
 cp -r ../../gtk2_ardour/icons/cursor_* ${Shared}/icons/
 cp ../../gtk2_ardour/ArdourMono.ttf $Shared

tools/osx_packaging/osx_build

@@ -472,6 +472,7 @@ cp $BUILD_ROOT/gtk2_ardour/clearlooks.rc $Resources
 
 mkdir ${Resources}/icons
 mkdir ${Resources}/resources
+cp ../../system_config $Resources/system_config
 cp ../../gtk2_ardour/icons/*.png ${Resources}/icons/
 cp -r ../../gtk2_ardour/icons/cursor_* ${Resources}/icons/
 cp ../../gtk2_ardour/ArdourMono.ttf $Shared

tools/x-win/package.sh

@@ -192,9 +192,6 @@ cp COPYING $DESTDIR/share/
 cp gtk2_ardour/icons/${PRODUCT_ICON} $DESTDIR/share/
 cp gtk2_ardour/icons/ArdourBug.ico $DESTDIR/share/
 
-#prefer built-in defaults
-rm -f $DESTDIR/share/${LOWERCASE_DIRNAME}/system_config
-
 # replace default cursor with square version (sans hotspot file)
 cp gtk2_ardour/icons/cursor_square/* $DESTDIR/share/${LOWERCASE_DIRNAME}/icons/