Use g_value_get_enum to create Go values from enums.

Fixes #39.
Add SetTitlebar support

closes #42
GValue to go value tranclation, refactor IdleAdd and TimeoutAdd

Closes #41.

Conflicts:
	glib/glib.go
	glib/glib_test.go
Fix import paths.
Improve binding coverage.

This change adds new bindings for the following GTK classes:

- GtkAboutDialog
- GtkAlignment
- GtkArrow
- GtkCalendar
- GtkDrawingArea
- GtkEventBox
- GtkSpinner
- GtkSwitch

In addition, new methods have been added for GtkLabel.

Initial work by @dajohi, cleaned up by @jrick.
Add missing GtkSwitch to cast function.
Prepare for release 0.2.0.
Remove (*Widget).IsVisible from GTK 3.6 build.
Add Go 1.2 to installation requirements.
Remove unused type.
Go fmt.
sync with conformal