Refactoring: replacement _pulp_client with pubtools-pulplib, removal of PulpAction classes

[rbikar]

Summary

Currently pubtools-pulplib does not support all required functionality for ubipop, but there were filed several tasks that will ensure pubtools-pulplib can be used within ubipop.
So the 1st goal of this issue is to remove _pulp_client.py and refactor code + tests so ubipop uses pubtools-pulplib lib for any manipulation, searching for units, etc. in pulp.

The 2nd goal of this issue is to refactor usage of PulpAction class and its subclasses. I think it should removed and places where it is used should be refactored.

Issue Type

• Feature Request

Current behavior

Currently ubipop uses it's own implementation of pulp client.
There are PulpAction classes that encapsulates un/association on pulp but they doesn't seem to make sense after pulp_client in ubipop is replaced with pubtools-pulplib

Desired behavior

• _pulp_client.py is completely removed -> related code is refactored using pubtools-pulplib
• PulpAction class and its subclasses are refactored or removed and related code is also refactored accordingly
• there are no regressions in code, no changes and functionality.

[rbikar]

Fixed in #223

Closing.