Generate PDF using XeLaTeX
travis: Install xetex and gyre
conf.py: LaTeX font size is 10pt
Merge pull request #449 from hflynn/java6min_develop

Making Java 1.6 minimum version required
omero: Python 2.6 is the minimum supported version
merge develop -D org -I include -E exclude: PR 369 (Cpp: Correct content and markup)
merge develop -D org -I include -E exclude: PR 437 (Generate PDF using XeLaTeX)
merge develop -D org -I include -E exclude: PR 448 (Managed repository)
merge develop -D org -I include -E exclude: PR 450 (omero: Python 2.6 is the minimum supported version)