BUG: initialize m_SmallBlock ivar in ctor; fixes garbage read

fixes clang ubsan error in itkGPUReductionTest test:
Modules/Core/GPUCommon/include/itkGPUReduction.hxx:225:20: runtime error: load of value 170, which is not a valid value for type 'bool'

Initialized a couple of other ivars while I was there.

Change-Id: I95b193876386cc7ca42f0807d2a8e9b75e76a6e1
BUG: changed some variables involved in shifting to unsigned

fixes clang ubsan error in itkGE4 test:
Modules/IO/GE/src/itkGE4ImageIO.cxx:375:29: runtime error: left shift of negative value -2113929216

Also:
- removed unused #defines
- removed useless casts
- put declarations with initializations.

Change-Id: Iab8d861afcc912934ac0bd7df486950fc59d4174
COMP: Fixed libminc to build on Windows

COMP: Improved MINCIOTransform tests

Updated to latest  version of libminc and added support
for reading compressed minc1 files (when using latest version of libminc only,
compiled with netcdf)

Change-Id: Ia01d21634d05fac38830c8d426567c40b6bd574e
Merge topic 'ubsan-fixes'

830538d BUG: changed some variables involved in shifting to unsigned
bd2c342 BUG: initialize m_SmallBlock ivar in ctor; fixes garbage read
Merge topic 'LIBMINC_UPDATE'

14d5b22 COMP: Fixed libminc to build on Windows