Refactored the TIFF reader, add support for floats

Fairly big refactoring of the TIFF reader, use templated methods in
many more places, avoid loss of type after it is determined, added
support for reading in 32 bit float TIFFs.

Change-Id: I4abf61179461acfa04c2c17c4e6d20467587c984
Added progress updates when reading a volume

Updating progress per page seems to give reasonable updates.

Change-Id: I142f5e18fad8294df2367d82bea171567c005fa5
Remove redundant checks for old JPEG compression

As Robert Maynard pointed out we already control for this in the
CanRead function, and so there is no need to repeatedly verify this
on every volume or tile read.

Change-Id: I47247928503c3e070a3905950fd726a2392c281a
Merge topic 'tiff-reader-update' into master

c2a7f9ff Remove redundant checks for old JPEG compression
fd35d0a3 Added progress updates when reading a volume
1fd42d60 Refactored the TIFF reader, add support for floats