taglist: API: Add HOMEPAGE tag

This tag will list a homepage for the media,
i.e. the artist's or movie's homepage.

This is different to GST_TAG_LOCATION as the latter
lists the original location of the media.

Fixes bug #571227.

docs/gst/gstreamer-sections.txt

@@ -2012,6 +2012,7 @@ GST_TAG_TRACK_COUNT
 GST_TAG_ALBUM_VOLUME_NUMBER
 GST_TAG_ALBUM_VOLUME_COUNT
 GST_TAG_LOCATION
+GST_TAG_HOMEPAGE
 GST_TAG_DESCRIPTION
 GST_TAG_VERSION
 GST_TAG_ISRC

gst/gsttaglist.c

@@ -156,6 +156,12 @@ _gst_tag_initialize (void)
       _
       ("Origin of media as a URI (location, where the original of the file or stream is hosted)"),
       gst_tag_merge_strings_with_comma);
+  gst_tag_register (GST_TAG_HOMEPAGE, GST_TAG_FLAG_META,
+      G_TYPE_STRING,
+      _("homepage"),
+      _
+      ("Homepage for this media (i.e. artist or movie homepage)"),
+      gst_tag_merge_strings_with_comma);
   gst_tag_register (GST_TAG_DESCRIPTION, GST_TAG_FLAG_META, G_TYPE_STRING,
       _("description"), _("short text describing the content of the data"),
       gst_tag_merge_strings_with_comma);

gst/gsttaglist.h

@@ -469,6 +469,14 @@ gboolean     gst_tag_list_get_date_index    (const GstTagList * list,
  * is hosted) (string)
  */
 #define GST_TAG_LOCATION               "location"
+/**
+ * GST_TAG_HOMEPAGE:
+ *
+ * Homepage for this media (i.e. artist or movie homepage) (string)
+ *
+ * Since: 0.10.23
+ */
+#define GST_TAG_HOMEPAGE               "homepage"
 /**
  * GST_TAG_DESCRIPTION:
  *