Add pip installation option for QCG-PJ on compute nodes

[arabnejad]

Currently, QCG-PilotJob package is installed in a python virtualEnv on the target remote machine. This approach will be useful if we don't have internet access on the compute node.

I think providing pip installation of QCG-PJ (in user's home space) on the compute node would be a good idea and gives more flexibility to users.
The idea is that: if users want to call QCG-PJ from the virtual environment, venv=True flag should be added to the command line, otherwise, it will automatically be called from the user's Python packages.

[arabnejad]

This can be closed by 1ecbaf9