[gtksourceview] docs: explain why gtk_source_space_drawer_new() is useful

[Sébastien Wilmet <swilmet src gnome org>]

commit 05734b4ca0478c68bb9ee7a90ca622eb34275ef7
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Oct 7 11:27:02 2016 +0200

    docs: explain why gtk_source_space_drawer_new() is useful
    
    There is no gtk_source_view_set_space_drawer() function, so it might be
    strange that the constructor of SpaceDrawer is public. So explain why it
    is public.

 gtksourceview/gtksourcespacedrawer.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)
---
diff --git a/gtksourceview/gtksourcespacedrawer.c b/gtksourceview/gtksourcespacedrawer.c
index b392be8..e252746 100644
--- a/gtksourceview/gtksourcespacedrawer.c
+++ b/gtksourceview/gtksourcespacedrawer.c
@@ -370,6 +370,9 @@ gtk_source_space_drawer_init (GtkSourceSpaceDrawer *drawer)
 /**
  * gtk_source_space_drawer_new:
  *
+ * Creates a new #GtkSourceSpaceDrawer object. Useful for storing space drawing
+ * settings independently of a #GtkSourceView.
+ *
  * Returns: a new #GtkSourceSpaceDrawer.
  * Since: 3.24
  */