shrink size of xdmf3 written files

thanks Andrew Burns for the patch.

Change-Id: I0efe48c0f43651e0da0fef036fa9e729d11c2a92
Adding in SimulationTimeStep output for particle paths.

Change-Id: I40ec0b8799bb009c256bf662dcc272fbef706b8e
Make sure molecule mapper works with depth peeling

Imposters use FragDepth as opposed to FragCoord.z

Change-Id: If376c2cb3c0dc8f1513b2712690d773afea4027a
Fix lighting to use Blinn-Phong specular model

A few fixes and cleanups. Use the Blinn-Phong specular lighting
model in the LightKit and Positional shaders. Old OpenGL uses this
model and it is a decent model. Remind myself that the camera is
positioned at 0,0,0 in view coordinates, had to fix a couple places
that were making different assumptions.

Minor changes to TestVBOPLYMapper to make it easier to use
when testing out changes.

Minor warning and documentation fixes as well.

Change-Id: I8bf108ec18fef2f0a2f83ada8cdf7663086036be
Fixed smart volume mapper crashes because of gradient opacity

Change-Id: Iea8c3f44371b0d62cc87063df138014c88c57c70
Fixed smart volume mapper level test

Change-Id: I0e6725b4522b3b82d6d0850082b350eef2c65aea
Added partial/initial support for Cocoa ARC memory management

Did this by creating #defines indicating if GC, MRR, or ARC, then excluding
retain/release/autorelease as necessary in the non-MRR case.

For the MRR case, there is really no change here.

For the GC case, retain/release/autorelease are nop at runtime,
but now they are excluded at compile time, so significant change.

For ARC, this fixed some (but not all) compiler errors, since
retain/release/autorelease cannot be called explicitly, and now aren’t.

Also fixed clang static analyzer (false positive) warning by reworking
memory management in InternalCreateTimer()/InternalDestroyTimer() a bit.

All this is necessary but insufficient. More to come.

Change-Id: I5666a01d8ed258c63f5415e4a381ea629a12ec7a
Merge topic 'fix_smartvolume_mapper_crashes' into master

7c3dc82c Fixed smart volume mapper level test
d296e253 Fixed smart volume mapper crashes because of gradient opacity
Added GDAL based raster reader

Co-authored by Jacob Becker <jacob.becker@kitware.com>. This reader support
a variety of rster formats using GDAL library

Change-Id: I9bc4dac89e271f307de70e86f0b50604d6229926
Fixed various minor issues

Change-Id: Iee65eba1254d6b7c6ad16072641fd405bc34a874
Added baseline and data for the testing

Change-Id: I67d54fb02b381f5c8b5a1d5dfdc245f741395b0e
Addressed minor code clean up issues

Change-Id: I620be35bdc580d7c59eb479f5070ea6ea45be0e8
Fixed various cleanup issues

Change-Id: Ie03440f350fd2e4add1c6f9f29d5e85e43762454
Merge topic 'cocoa-arc' into master

dd3f20db Added partial/initial support for Cocoa ARC memory management
Merge topic 'molucule_depth_peeling' into master

85666eb9 Make sure molecule mapper works with depth peeling
Reduce the size of the test it was too big for my macbook

macbook with retina display by default can only show up to a
690 pixel tall window because it does pixel doubling by default and
it has a title bar. 1400 - title bar / 2 is < 700.

Also a minor fix to release texture resources more quickly on
the imageslicemapper.

Change-Id: I6421807cbb3e7bd048c333909c18f6a95d21d662
Merge topic 'lighting_fixes' into master

c97d617e Fix lighting to use Blinn-Phong specular model
Merge topic 'fit_test_to_macbook' into master

03efc593 Reduce the size of the test it was too big for my macbook
Add valid image for other systems (not AA etc)

Change-Id: Ibba2985c795b0f3c8f9355da617bd7f90eec67f1
Merge topic 'valid_image' into master

8cf31408 Add valid image for other systems (not AA etc)