[glib: 1/2] gdatetime: Document RFC 3339 extensions when parsing ISO 8601

[Philip Withnall <pwithnall src gnome org>]

commit ea98aab57bdb3741a49e92a07f1d3ce22342e482
Author: Philip Withnall <philip tecnocode co uk>
Date:   Thu Oct 10 14:06:13 2019 +0000

    gdatetime: Document RFC 3339 extensions when parsing ISO 8601
    
    This is a follow-up to !1017.
    
    Signed-off-by: Philip Withnall <withnall endlessm com>

 glib/gdatetime.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)
---
diff --git a/glib/gdatetime.c b/glib/gdatetime.c
index 3be4eba3d..1382d3f93 100644
--- a/glib/gdatetime.c
+++ b/glib/gdatetime.c
@@ -1429,9 +1429,13 @@ parse_iso8601_time (const gchar *text, gsize length,
  *
  * Creates a #GDateTime corresponding to the given
  * [ISO 8601 formatted string](https://en.wikipedia.org/wiki/ISO_8601)
- * @text. ISO 8601 strings of the form <date><sep><time><tz> are supported.
+ * @text. ISO 8601 strings of the form <date><sep><time><tz> are supported, with
+ * some extensions from [RFC 3339](https://tools.ietf.org/html/rfc3339) as
+ * mentioned below.
  *
- * <sep> is the separator and can be either 'T', 't' or ' '.
+ * <sep> is the separator and can be either 'T', 't' or ' '. The latter two
+ * separators are an extension from
+ * [RFC 3339](https://tools.ietf.org/html/rfc3339#section-5.6).
  *
  * <date> is in the form:
  *