[Piglit] [PATCH v3 0/5] Revised isinf/isnan test, and piglit infrastructure improvements

[Paul Berry]

Ok, here is attempt #3 on the isinf/isnan test and related
patches.  The test itself is the same it was in the v2
series (sent 10/7), but the supporting infrastructure has
improved:

- piglit_require_gl_version() now takes an integer argument
  representing 10 times the required version (e.g. 31 means
  OpenGL 3.1).  This avoids having to be tricky about locales and
  rounding errors.

- I've also modified piglit_get_gl_version() to use the same
  format for consistency, and created a separate function,
  piglit_is_gles(), to do the other job that it was
  doing (checking whether the API is GL ES).

- And I've fixed several Glean tests that previously checked
  GL_VERSION directly using logic that was way too specific (for
  example, some tests only ran when the version was 2.0, 2.1, or
  3.0.  Now those tests run whever the version is at least 2.0).

[PATCH v3 1/5] Make it possible to include piglit-util.h from C++ programs
[PATCH v3 2/5] Split piglit_get_gl_version() into two functions.
[PATCH v3 3/5] Add a piglit_require_gl_version() function.
[PATCH v3 4/5] Fix too-specific GL version checks in glean
[PATCH v3 5/5] Add a test of isinf() and isnan() functionality.