fix the last bugs in the GregoryBoundary EvalLimit CPU kernel
fix cpuEvalLimitController : some samples were being dropped because
of bad parameterization on non-quad faces
bug fix in limitEval example : calculation for the required number of samples was incorrect
on geometry with non-quad faces. This should be fixed now.
doc fix for EvalLimitSample
Moving some member variables of OsdGlDrawContext from public to protected
and adding the requisite accessors

Note : all our example code goes through the same boiler-plate texture
binding code - we might want to move it as a member function of the DrawContext.
Added early exit to Refine method to avoid unnecessary interop.
- prevent corner gutter texels from going into an infinite loop by
  adding an arbitrary break if vertex valence is > 256

- add a Warning function to Osd error reporting

- minor cleanup /refactor / document of OsdError

fixes #167
Release 1.2.2
Merge branch 'release/1.2.2' into dev
Fix fvardata interpolation on adaptive patches.
If Hbr carries no fvar data, then we shouldn't attempt to build fvar data tables in Far,
where the factory requests it or not...

fixes #169
Fix cmakefile and #ifdefs for opencl configuration.
- adding varying data interpolation to the EvalLimit module

- minor refactoring of the LimitEvalContext to accomodate all the data buffers

- pushing some minor sub-patch functionality back to FarPatchParams

- extend example code with randomly generated varying vertex colors
Fix bug : multi mesh wasn't working correctly. FarMultiMesh has to set meshIndex to FarKernelBatch.
fixes #170
first pass at face-varying interpolation for CpuEvalLimit - still
a couple of kinks to be worked out...
evalLimit example : make sure to reset the output buffer on creation - some of the prims may not
set all the point colors (if face-varying data is missing on the test shape for instance)
and we don't want random values creeping from unset memory allocations.
shape_utils : make sure we don't create a mesh with face-varying data declared
if the shape does not actually contain usable face-varying data.
- fix a face-varying bug in shape_utils : now face-varying UVs are indexed correctly
  coming out of our shape format

- set blue component of point-cloud to 0 in face-varying mode (save a few micro-secs)
- add a message to limitEval when trying to display face-varying UVs on shapes
  that do not have that type of data

- fix some regression shapes that had "empty" uv values
  (including some minor topo surgery that luckily appears to not break
  regression baselines)
fix FarPatchTables::IsFeatureAdaptive() :
- trivial return if Gregory specific patch data is set
- or iterate through the patch-arrays until an adaptive patch is found (REGULAR,...,GREGORY_BOUNDARY)

fixes #173