[dev-python/pygobject*] provide split ebuilds version of pygobject

dev-python/pygobject[cairo] is starting to be required for several
graphical application that otherwise fail to run at runtime. The
list of apps includes the in-development Entropy Rigo Browser.
Unfortunately, dev-python/pygobject[cairo] pulls in a shitload
of deps: half X -> mesa -> llvm/clang. This is unwanted on
X-less images we have (SpinBase) due to the big amount of extra
software we would have to ship with.
We cannot remove dev-python/pygobject from ISO images because
Anaconda requires it.

dev-python/pygobject/pygobject-3.0.4.ebuild

@@ -0,0 +1,18 @@
+# Copyright 1999-2012 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+# $Header: $
+
+EAPI="4"
+
+DESCRIPTION="GLib's GObject library bindings for Python, meta package"
+HOMEPAGE="http://www.pygtk.org"
+
+LICENSE="LGPL-2.1"
+SLOT="3"
+KEYWORDS="~alpha ~amd64 ~arm ~hppa ~ia64 ~mips ~ppc ~ppc64 ~sh ~sparc ~x86 ~x86-fbsd ~x86-interix ~amd64-linux ~x86-linux ~ppc-macos ~x64-macos ~x86-macos ~sparc-solaris ~x64-solaris ~x86-solaris"
+IUSE="+cairo examples test +threads" # doc
+
+COMMON_DEPEND="
+	~dev-python/pygobject-base-${PV}[threads=,examples=,test=]
+	cairo? ( ~dev-python/pygobject-cairo-${PV}[threads=] )"
+DEPEND="${COMMON_DEPEND}"