Port warning and style fixes from VolumeOpenGL2

This change fixes unused-but-set-variable warnings.
It also addresses disparate conventions in shader code.

Change-Id: I4c8f3ede7ca853153d5ad217cdf956203fb4fcb7
ENH: Sorted out python and tcl tests for new volume rendering

Change-Id: I11687b45b3d196c7f1fa7e164ac8c2d62151c5aa
Added a new example demonstrating developing SMP algorithms.

Added SMP contour algorithm. Also demonstrating how additional
TBB functionality can be exposed.

Change-Id: I2c328d72cade31ee736c199dc62ea4522c4b8635
Merge topic 'volumeopenglnew_fixes' into master

857241a0 Port warning and style fixes from VolumeOpenGL2
Remove bad transpose of normal matrix

Change-Id: If552d5b54384a78106af56c06127b63b4d6005a1
Merge topic 'glyph_lighting_fix' into master

6128ad44 Remove bad transpose of normal matrix
Added another SMP example.

Added example of multi-threaded streaming using executives.

Change-Id: I8c94b78e36fe94de94533b5b97580b6b2560e97e
Merge topic 'volume_rendering_python_tcl_tests' into master

a8c11177 ENH: Sorted out python and tcl tests for new volume rendering
Merge topic 'smp-contour-example' into master

c3b9d7b5 Added another SMP example.
d9e442f2 Added a new example demonstrating developing SMP algorithms.