Moved FontSetup and two helper classes from render.pdf to fonts package.

Moved FontSetup and two helper classes from render.pdf to fonts package.
FontSetup has the PDF fonts as the default, but this class can be extended
if/when another renderer needs its own font setups.  (Cannot do this, however,
for AWT's FontSetup at the moment, because its setup() has a different
signature.)

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@197031 13f79535-47bb-0310-9956-ffa450edef68