[gnome-shell/wip/nielsdg/cleanup-plugin-boilerplate: 207/210] plugin: Add some comments on its purpose

[Niels De Graef <nielsdg src gnome org>]

commit e7a279737e70a47e57e38200be4376c3f8c9e74f
Author: Niels De Graef <nielsdegraef gmail com>
Date:   Tue Dec 25 15:40:10 2018 +0100

    plugin: Add some comments on its purpose
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/315

 src/gnome-shell-plugin.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/src/gnome-shell-plugin.c b/src/gnome-shell-plugin.c
index fa8410d40..5ed8e553e 100644
--- a/src/gnome-shell-plugin.c
+++ b/src/gnome-shell-plugin.c
@@ -21,6 +21,16 @@
  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
+/*
+ * GnomeShellPlugin is the entry point for for GNOME Shell into and out of
+ * Mutter. By registering itself into Mutter using
+ * meta_plugin_manager_set_plugin_type(), Mutter will call the vfuncs of the
+ * plugin at the appropriate time.
+ *
+ * The funcions in in GnomeShellPlugin are all just stubs, which just call the
+ * similar methods in GnomeShellWm.
+ */
+
 #include "config.h"
 
 #include <stdlib.h>