* Created p4runtime exercise directory with draft P4 program
* Updating VM
- Adding p4 to vboxsf group for VirtualBox Shared Folders
- Adding gRPC Python package for p4 runtime
- Setting up VM to use 2 CPUs
* Updating .gitignore for PyCharms and Mac OS
* Adding P4RuntimeSwitch type and support in run_exercises
If the grpc switch target is used, we will instantiate a P4RuntimeSwitch.
Ideally, this will get merged with BMv2's P4Switch and can be removed
* Adding p4 runtime and p4info browser libraries
Also, adding a Makefile for this project
