Gatan DM2: fix the pixel type for 32-bit data
(cherry picked from commit 6ccc87d3910864914ac4ef3218b58c95dd4b3ebe)
Gatan DM2: ignore negative-length strings
(cherry picked from commit 8bf6c6ea210a061e9bf73570e6388f5fda7ade2d)
Gatan DM2: parse more metadata from the "extra tags" section
(cherry picked from commit e66a116b27898d54911bf842fd3c055fe37f1484)
TIFF: fix header writing for big-endian BigTIFF files

Fix suggested by Matthias Baldauf:

http://lists.openmicroscopy.org.uk/pipermail/ome-users/2012-November/003463.html
Re-arranging user pages re ticket 7208
Actually fixing managing memory page!
Managing memory page take 3! (ah Friday)
It is fixed this time honest!
Final format and style fixing - conflict fix

Conflicts:
	docs/sphinx/developers/reader-guide.txt
	docs/sphinx/developers/using-bioformats.txt
Making folders lowercase & moving imagej & fiji
Fixing folder names properly!
Increase the depth level of the PDF table of contents
Remove extra other applications heading
Reducing nesting & Curtis's edits
Adding visual_analysis/imago
Fxing vaa3d link
Adding vaa3d.org to linkcheck ignore
sorting user urls/structure & indexes
Fixing parts for pdf
Fixing premature commit links