`HpBaseWorkChain`: implement restart from last q point `process_handler`

[bastonero]

Currently, the hp.x code does not support restart features. Nevertheless, the code is able to stop smoothly at a given q point. Thus, a process_handler can be implemented in the HpBaseWorkChain to handle this issue.
This implementation would require at least:

• Modifying the HpParser to be able to detect the error, the exact q point in which it finished, and the remaining ones to compute.
• Modifying the HpCalculation to support the start_q , last_q and sum_pertq.
• Implementing the process_handler in the HpBaseWorkChain.

Note that this can be done ONLY when perturb_only_atom is used.

In principle one should also be able to write a new HpParallelizeQpointsWorkChain, for which every q points is computed. Nevertheless, currently the hp.x code does not support an initialization run printing the q points that will compute (even when setting iverbosity=3 or higher).