Straxify strax interface

[jmosbacher]

What is the problem / what does the code in this PR do
Strax interface plugin implements its own configuration management, bypassing the strax config management. This results in many hacks and unneeded complexity when generating the strax context. I assume this was done because of the large number of config options and their historical loading from config files.
The overlapping of config names between fax configuration and straxen processing plugins (for obvious reasons) creates two main issues:

1. Changing fax config values wont change the raw data hash, requiring the creation of "simulation run ids" to define different fax settings.
2. Having divergent configuration for waveform generation and processing is difficult and requires hacks that depend on straxen internals which may change and break everything.

This PR is an experiment on whether we can use strax config management for all fax configs and remove the set_config() method.

The implementation is still a work in progress, it may take some time to get a working prototype.