[tepl] docs: improve doc of TeplTab

[Sébastien Wilmet <swilmet src gnome org>]

commit 63a31536b60094d1e70c7baa02e443b36137ee6a
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Jul 28 11:11:50 2017 +0200

    docs: improve doc of TeplTab

 tepl/tepl-tab.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/tepl/tepl-tab.c b/tepl/tepl-tab.c
index 1ee430f..4614de8 100644
--- a/tepl/tepl-tab.c
+++ b/tepl/tepl-tab.c
@@ -27,10 +27,15 @@
  * SECTION:tab
  * @Short_description: Contains a TeplView and GtkInfoBars
  * @Title: TeplTab
+ * @See_also: #TeplInfoBar
  *
  * #TeplTab is meant to be the content of one tab in the text editor (if the
  * text editor has a Tabbed Document Interface). It is a #GtkGrid container that
- * contains the #TeplView and can contain one or several #GtkInfoBar's.
+ * contains the #TeplView and can contain one or several #GtkInfoBar's. Since it
+ * is a #GtkGrid, an application can of course add any other widget to it.
+ *
+ * To create a new #GtkInfoBar, it is recommended to use #TeplInfoBar (but
+ * #TeplTab doesn't enforce it).
  *
  * By default:
  * - #TeplTab has a vertical #GtkOrientation.