Trac #15561: freetype 2.3.5 is too old for some fonts of current systems.

The now-current freetype library has problems with newer fonts. This
forbids its uses in some applications on machines having system fonts
not supported by this version.

This was diagnosed on sage's R (see
[https://groups.google.com/forum/#!topic/sage-support/FnTEcpfg6wE this
thread]) by Volker Braun.

A stopgap measure is to upgrade freetype to a more forgiving version of
freetype, hence this ticket.

The current freetype tarball hits a snag in libpng, because it uses
setjmp for exception handling, which triggers a compiler error due to
this settinng up been made twice. So a small patch to the current libpng
is part of this branch.

New tarball: http://download.savannah.gnu.org/releases/freetype/freetype
-2.5.2.tar.bz2

URL: http://trac.sagemath.org/15561
Reported by: charpent
Ticket author(s): Emmanuel Charpentier, Volker Braun
Reviewer(s): Volker Braun
Trac #15564: Doc misformatting in toric varieties

While building the docs, I noticed
{{{
[schemes  ] /home/king/Sage/git/sage/local/lib/python2.7/site-
packages/sage/schemes/toric/library.py:docstring of
sage.schemes.toric.library.ToricVarietyFactory.torus:7: WARNING: Inline
interpreted text or phrase reference start-string without end-string.
}}}

URL: http://trac.sagemath.org/15564
Reported by: SimonKing
Ticket author(s): Simon King
Reviewer(s): Volker Braun
Trac #15566: The -sync-build option is broken

URL: http://trac.sagemath.org/15566
Reported by: vbraun
Ticket author(s): Volker Braun
Reviewer(s): Nathann Cohen