New widget to time the execution of a single filter

I've built an observer that attaches to a vtkAlgorithm and listens
for StartEvent and EndEvent.  It records both CPU and wall clock time
between those two events using vtkTimerLog.  Afterward you can retrieve
the elapsed time in a couple of ivars.  You can also subclass it and
do anything you like once the filter finishes execution.

Change-Id: I96977da18d0ffd730660c9b5c1d8bfa1f07623e9
Add test for vtkExecutionTimer

Change-Id: Iabae07c03d6bb11b4f5dc8b426ac68a743610b87
Add a vtkPath class to represent lines and Bezier curves.

Change-Id: Ie6fd3f46efc1000c517e8386aeda9328bc6307d8
Add API to generate vtkPath data and colored images from MathText.

* Add API to produce a vtkPath representing contours of math text.
* The vtkMathTextUtilities API now accepts vtkTextProperties to
  set colors, font size, etc.
* Make MathTextUtilities abstract (The matplotlib module overrides
  this class in a later commit)
* Remove python dep from vtkMathText.

Change-Id: Id4d9fb91be831673d13b865802c24f230f263820
Add MathText drawing functionality to Context2D classes.

Change-Id: I1168be82fb0a1f5d9a2a08c86801531945f867dc
Add vtkMathTextActor for rendering equation overlays.

Change-Id: I02b4376726ba87d2d6bedffc9ac67d56d5066c34
Add vtkMathTextActor3D for rendering equations in 3D space.

Change-Id: If11d17e914b1af5607237f7c6e8b08bd97aee29b
Bump included gl2ps sources to v1.3.6.

Includes a modification to the gl2psTextOpt function which
adds a color option.

Change-Id: I467b56dd870a3e87054b42125e373f0c0baad387
Add support for gl2psSpecial with PDF output to gl2ps.

Change-Id: I2229456ad3f254869d34009143b17eadcac8c7bf
Update vtkGL2PSExporter, add Rendering/GL2PS module

* Fixed bitmap rasterization.
* Added ability to exclude specific 3D props from the rasterization
  process, if enabled.
* Improved support for text rendering.
* Added method to vtkRenderWindow to collect all visible
  vtkActor2D objects that are vtk[Math]TextActors or use a
  vtkTextMapper.
* Add support for Context2D drawings
* Add CMake/CompareFileMD5.cmake script to compare postscript files
* Remove old GL2PSExporter python test
* Modify gl2ps sources to disable writing timestamps (prevents
  useful MD5 hashing for regression tests)
* A static string is used as the image title by default.
* Add vtkGL2PSUtilities, a collection of static functions that
  interact with GL2PS to render vtk objects.
* Add a gl2psGetFileFormat() function to the bundled gl2ps library.

Change-Id: Ia6fafc8e4d0a49bd9fdbecf32f43925a0aab7050
Add a vtkMatplotlib module.

* Isolates python dependency away from MathText
* Adds tests for MathText functionality.

Change-Id: Ib0f87248e7f73ead5d1904b72e7053537907bfd1
Add a GL2PS special case for vtkTextActor3D.

This implements a vtkFreeTypeTools::StringToPath method that
generates path data describing the outline of a rendered text
string. This path gets transformed to match the vtkTextActor3D's
appearance, then projected into 2D and drawn to the GL2PS buffer.

Change-Id: I2513a9d03799f290688624dd09f419def03e2996
Add functions to check if MathText is available at runtime.

bool vtkContext2D::MathTextIsSupported()
bool vtkContextDevice2D::MathTextIsSupported()
bool vtkMathTextActor::IsSupported()
bool vtkMathTextActor3D::IsSupported()

Availablity of MathText can also be check from anywhere using
vtkMathTextUtilities::GetInstance() != NULL.

Change-Id: I288bc94ddfdda578edb2f4618035de68db3c583f
Add missing return statements to tests.

Change-Id: I2890e67e383f8af88a9175e4497c5167c6d22468
Clean up some compiler warnings on Mac and Windows.

Missing cases for switch on enum, unused parameters.

Change-Id: I4ea2ae779e0f8ab0b4b9a3220798113ae1d98c42
vtkAMREnzoReaderInternal: Fix include order for AIX streams

VTK headers define preprocessing macros for large file support that
affect AIX stream headers.  Include them first to ensure streams are
compatible with other translation units in VTK.

Change-Id: I34db467b927fb19325781aada4b15c690412345c
Move FontConfig font lookup to its own module.

This removes the VTK_USE_FONTCONFIG option and is more consistent
with the modular approach.

Change-Id: Iaa7383667b116a0e9b596f9467b824710e865b5f
Incorporate Andrew Maclean's style&comment suggestions

1) VTK-style comments on all the methods in the .h file.  I have
no idea what I was thinking (or not) when I forgot to do these.

2) Copyright changed from Sandia to VTK standard.

3) Added #include <cstdlib> to TestExecutionTimer.cxx to make sure
EXIT_SUCCESS is defined.

4) Condensed the output from the test.

5) Replace the guts of the test with the guts of the vtkDelaunay2D
test so that it takes a little while longer.

6) Switch the output to 8 digit fixed precision to make it much
less likely that times will be rounded to zero.

Change-Id: Ic6b86fc5645d979fbeacca22f8bb68990ecc3890
Move #include "vtkExecutionTimer.h" to the top of the list

Per Andrew Maclean's suggestion, that particular #include is now
at the top of the list and set apart by whitespace.  Let there be
no doubt at all about what's being tested!

Change-Id: I5c87695dcf9f966f570d749622402d958998ffb0
Merge 'VTK/master' into MathTextGL2PS

Resolved Conflicts:
	Rendering/MathText/vtkMathTextUtilities.cxx
          * Header changes clashed

Change-Id: I3513fe9e07af2f6c161a8222f02badebee3feda1