markup: scale the shift of super/sub-scripts by font-size
slurs avoid stafflines: move far enough; issue 3628
documentation: staff-spacing, resolve collisions
Issue 3712: Ponding about Turkish Ebook by Server Acim

See
<URL:http://lists.gnu.org/archive/html/bug-lilypond/2013-12/msg00051.html>
for the announcement.
Remove outdated dependencies on .pfa files, replace with .pfb where feasible.

This may be related to issue 3674: Multiprocessor builds fail on some platforms.