EbuildBuild: handle empty PORTAGE_BINPKG_FORMAT

Also, make TaskSequence._start_next_task() call exit hooks if the
queue happens to be empty.

X-Gentoo-Bug: 506186
X-Gentoo-Bug-URL: https://bugs.gentoo.org/show_bug.cgi?id=506186
make.conf.5: Fix order of some paragraphs.
Update RELEASE-NOTES
repoman: Add DESCRIPTION.puntuation check (bug #438976)

Basic patch supplied by Michael Orlitzky.
Modified to be easier to add/remove puntuation to the check.
repoman: Add ruby18 warning for deprecated ruby target
emerge/actions: Add python version to portage version line

Adds the currently running python version to the portage version line,
so that it's immediately obvious what version of python is being used to
run portage.
repoman: Add accidently deleted closing bracket ')'

Fixes commit: repoman: Add DESCRIPTION.puntuation check (bug #438976)
SHA: 06637c4215d55c57517739214c6e0fd6f8f53914
Date: (Fri Apr 18 21:55:56 2014)
Merge git://git.overlays.gentoo.org/proj/portage into 2013-12-02

Conflicts:
	pym/_emerge/actions.py