Populate new Pixels values in the 2013-06 schema
Change *PixelsBinDataBigEndian to populate/retrieve Pixels.BigEndian

This allows the correct attribute to be populated without having to
remove setPixelsBinDataBigEndian and getPixelsBinDataBigEndian (which
are used widely).
Parse magnification values as doubles

NominalMagnification is now an xsd:float in the schema, so it doesn't
make sense to parse and/or cast the magnification values to integers.
Add a MetadataOnly element

This replaces the BinData element that was previously created during
population of the "BigEndian" attribute.
xsd-fu: Move Timestamp to PRIMITIVE_TYPE_MAP
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 594 (Remove plonematch theme from Bio-Formats documentation (rebased onto develop))
merge develop -D org -I include -E exclude: PR 595 (gen-meta-support: reverse XML entity sorting)
merge develop -D org -I include -E exclude: PR 596 (Minor defensive programming changes for TIFF-based formats)
merge develop -D org -I include -E exclude: PR 597 (Update OME-XML population to match 2013-06 changes)