some g_time_val methods are unwrapped.

[Krzesimir Nowak <qdlacz gmail com>]

Hi.

I was using Glib::TimeVal and I wondered if is there a way to convert
this structure into Glib::ustring. Glib::TimeVal has no such methods,
but in Glib there is a function named g_time_val_to_iso8601, which
returns a string containing an iso8601 date.

Generally speaking two functions aren't wrapped:
g_time_val_to_iso8601
g_time_val_from_iso8601

Second one maybe could be wrapped as a constructor of Glib::TimeVal.
Should I file a bug in bugzilla? I could possibly provide a patch.

Krzesimir Nowak.