Document standard macros and functions
Submitted by Damon Chaplin
We need to document the standard macros like these:
GTK_ABOUT_DIALOG GTK_IS_ABOUT_DIALOG GTK_TYPE_ABOUT_DIALOG
GTK_ABOUT_DIALOG_CLASS GTK_IS_ABOUT_DIALOG_CLASS GTK_ABOUT_DIALOG_GET_CLASS
(gtk_about_dialog_get_type? - maybe we only show it if a macro like GTK_TYPE_ABOUT_DIALOG isn't defined for the widget)
I suggest placing them as a group at the bottom of the Synopsis, with links to a page in the GObject docs that describes them.