GtkRcPropertyParser for use with gtkSettingsInstallPropertyParser
or gtkWidgetClassInstallStylePropertyParser which parses a
color given either by its name or in the form
{ red, green, blue } where red, green and
blue are integers between 0 and 65535 or floating-point numbers
between 0 and 1.gtkRcPropertyParseColor(pspec, gstring)pspecgstringcharacter to be parsed