Merge pull request #594 from sbesson/rebased/develop/theme_cleanup

Remove plonematch theme from Bio-Formats documentation (rebased onto develop)
Merge pull request #595 from melissalinkert/autogen-performance

gen-meta-support: reverse XML entity sorting
merge develop -D org -I include -E exclude: PR 528 (Tile performance improvements for VMS and NDPI)
merge develop -D org -I include -E exclude: PR 583 (Reduce the number of JAI ImageIO registrations)
merge develop -D org -I include -E exclude: PR 589 (Zeiss LSM: use the longer display channel name)
merge develop -D org -I include -E exclude: PR 590 (xsd-fu: Generalise language type mapping (3))
merge develop -D org -I include -E exclude: PR 596 (Minor defensive programming changes for TIFF-based formats)