Try to make points() a little less heavyweight

[agcapps]

This starts to remove the type insurance code since we are fairly sure we will get index_t. Needs testing.

[agcapps]

@cyrush , @aaroncblack and I talked about this routine. It seems this takes most of the time in a run he is interested in, so this was a first pass at speeding things up. Please let me know if this is starting to go down the right path.

[cyrush]

This should certainly help. This is one of those areas that is using std::set as well. I assume the algorithm relies on that to de-duplicate. Do the set operations show up in profiles?

[cyrush]

Seems like there is an indexing issue.

unknown file : error : C++ exception with description " [D:\a\conduit\conduit\build\RUN_TESTS.vcxproj]
  file: D:\a\conduit\conduit\src\libs\conduit\conduit_node.cpp
  line: 14021
  message: 
  Invalid child index: 0 (number of children: 0)
  " thrown in the test body.
unknown file : error : C++ exception with description " [D:\a\conduit\conduit\build\RUN_TESTS.vcxproj]
  file: D:\a\conduit\conduit\src\libs\conduit\conduit_node.cpp
  line: 14021
  message: 
  Invalid child index: 0 (number of children: 0)
  " thrown in the test body.
  [  FAILED  ] conduit_blueprint_mpi_mesh_transform.generate_sides (2 ms)
  [  FAILED  ] conduit_blueprint_mpi_mesh_transform.generate_sides (2 ms)
  [ RUN      ] conduit_blueprint_mpi_mesh_transform.generate_corners
  [ RUN      ] conduit_blueprint_mpi_mesh_transform.generate_corners
unknown file : error : C++ exception with description " [D:\a\conduit\conduit\build\RUN_TESTS.vcxproj]
  file: D:\a\conduit\conduit\src\libs\conduit\conduit_node.cpp
  line: 14021
  message: 
  Invalid child index: 0 (number of children: 0)
  " thrown in the test body.
unknown file : error : C++ exception with description " [D:\a\conduit\conduit\build\RUN_TESTS.vcxproj]
  file: D:\a\conduit\conduit\src\libs\conduit\conduit_node.cpp
  line: 14021
  message: 
  Invalid child index: 0 (number of children: 0)
  " thrown in the test body.

[cyrush]

@agcapps pushed a fix.

[cyrush]

@agcapps merging this, with the tweaks I made its ready to go.

[agcapps]

@cyrush Thanks for the fixes and for merging it in.