DOC: Describe how to get L and U out of the LU factorization.

Change-Id: I29821d396798f1d3d2208a891bcfa76d9cc51308
Shapefiles: If active layer specified, load only it.

Change-Id: Ic152c6878ea665ccc6e09baa993809b6f7c4ec77
OpenGL driver version detection and OS Mesa features

Added support to vtkOpenGLExtensionManager for fine grained
OpenGL driver version detection. Added a flag to enable/disable
features with known driver specific bugs for testing new
driver releases. This mostly to test future Mesa releases to
determine if bugs have been fixed. Used the new feature to
see if some long standing Mesa bugs have been fixed in newer
Mesa releases for the OS Mesa renderer.

* NPOT texture support used by vtkOpenGLContextDevice2D and
vtkOpenGL2ContextDevice2D fixed in Mesa >= 8

* reset glReadBuffer to quiet incomplete FBO error report in
vtkOpenGLVolumeGPURayCastMapper

* vtkOpenGLVolumeGPURayCastMapper tests pass in Mesa >= 9
except TestGPURayCastCompositeShadeMask. Explicitly disabled
the test for OS Mesa.

* disable FBO for Mesa < 8 because of TestBlurAndSobelPasses
TestSobelGradientMagnitudePass test failures

* disable vtkOpenGLHAVSVolumeMapper for OS Mesa without
Gallium llvmpipe renderer

* vtkCompositeRGBAPass needs GL_ARB_texture_float. Mesa
may or may not be built with it enabled due to patent
restrictions and a bug in 8-9 releases.

* Disable FBO for Mesa drivers reporting OpenGL version 1.4
because of incomplete/buggy GL_ARB_draw_buffers.

* Although associated ctests run and pass, disable
vtkOpenGLVolumeTextureMapper3D for OS Mesa < 9 because of
false OpenGL invalid enum report.

Change-Id: Ic82aeb4747137aead53251026744baa61ced66d0
Make "graphic error" api legacy

Decorated vtkRenderWindow "graphic error" methods with legacy.
These were superceded by vtkOpenGL{Check/Clear}ErrorMacro's.

Change-Id: I2b3fbbbb1125b7611d4553e6ea1640b3f74121f6
Fixed reference counting bug in vtkTransform

There was a reference counting error in vtkTransformConcatenation when
a transform was DeepCopy'ed and shortened and then DeepCopy'ed and lengthened
using some of the same concatenated transforms.

When the list of concatenated transforms was shortened, the values
were not cleared out, letting pointers in the list that did not have a reference
according to the reference counting.  Later, when the list was set to a larger
list again and happenned to have the same transform at postion x, since there
was already a reference to the transform in the list, it did not increment
the reference count even though it should have.  This commit fixes this
by setting pointers beyond the end of the list to NULL when DeepCopy shrinks the list.

This commit also adds a regression test for that will segfault unless the
bug is fixed due to a reference count that is accidentally decremented in
a loop due to the bug. Running this test without this patch will segfault.

Change-Id: I27d7c2097f85a2f8c1d6e8a0e8213d041cc83125
Merge topic 'gdal-active-layer' into master

8e5b524b Shapefiles: If active layer specified, load only it.
Merge topic 'opengl-error-hunt' into master

4d5cbfb6 OpenGL driver version detection and OS Mesa features
Merge topic 'legacy-graphic-error-api' into master

c544585c Make "graphic error" api legacy
Merge topic 'transform_reference_counting_bug' into master

b47332bb Fixed reference counting bug in vtkTransform
Merge topic 'LUDoc' into master

29bbbaf2 DOC: Describe how to get L and U out of the LU factorization.