remove unneeded tools from source tree

[hppritcha]

Several of the tools in this fork of PRRTe are no longer needed. Their removal will simplify merging the PRRTe source into the Open MPI repo proper.

In particular the code in the following folders can be removed

• https://github.com/open-mpi/prrte/tree/master/src/tools/pcc
• https://github.com/open-mpi/prrte/tree/master/src/tools/psched

You will also need to remove the examples directory.

Removal of these tools may result in some CI failures that may need to be addressed by tweaking the CI scripts.

Any related man page documentation pertaining to these tools should also be remove as part of the solution for this issue.

From a checkout of the full OMPI source code check in ompi/3rd-party/prrte/docs/man for man pages to possibly remove. Note not all prrte commands have corresponding man pages.