podman.py: simplified version with abstract methods

This is updated version of podman.py with much of complex
parameter management moved out of the utililty, now container
creation is simplified as most of the args are handled by user
and utility has abstract dict of args:values

Also removed redundant utils like multiple container creation
this can be handled at test level by calling run in for loop

also added support for creating and managing containers via
root and non root users

Signed-off-by: Abdul Haleem <abdhalee@linux.vnet.ibm.com>

Author: abdhaleegit