Prepare for release 0.1.1.
Initial support for GdkPixbuf.
Initial support for cairo Surface and Context.

This change adds a new gotk3 package for Cairo bindings.  Currently,
there exists support for Surface (cairo_surface_t) and Context
(cairo_t).

Symbols used have been limited to Cairo 1.10 and not the latest 1.12
because I don't feel like adding yet another build tag to complicate
the build process.

This is a step towards completing #33.
Fix a calloc call with correct binary size.
Remove Cairo 1.12 consts found by Travis-CI.
Add gtk.OffscreenWindow implementation and bindings.

Closes #33.
Add back a brace that went missing.
Update README to mention Cairo support.
Fix func signature for (*gtk.TreeModel).GetIterFirst.

GetIterFirst must return a bool false, rather than an error, if it
cannot create an iterator due to there being no items in the
TreeModel.

Fixes #34.
Added TreeModel.IterNext()
Extend and modify ListStore bindings.

This change adds the InsertBefore and InsertAfter bindings for
ListStore.  While developing these bindings, it was determined that
the correct way to pass unset iterators to cgo is to create them in
gotk3 code itself and return a pointer, rather than insisting the
caller know the difference between a set and unset iterator.
Use correct new function for TextTagTable.

Fixes #40.
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.