Add configuration file for different camera IPs and possible settings

[BenMoon]

It would be good to have a config file where the camera IP and possibly some other parameters could be defined.
Here's a proposal:

pymepix/etc/default.yaml

This file should keep the settings crucial to establish a connection between the computer and camera and set it up.

pc_ip = 192.168.1.1
tpx_ip = 192.168.1.10
sophy_config = 'path_to_sophy_config'

pymepix/etc/auto_save.yaml

This file should record the last used settings for a specific camera.
camera_name = 'W0006_H05'
    coarse_bias = 50
    fine_bias = 5
    threshold = 120
    sophy_config = 'pymepix/etc/H05.spx'
camera_name = 'W0006_I06'
    coarse_bias = 50
    fine_bias = 7
    threshold = 150
    sophy_config = 'pymepix/etc/I06.spx'

If settings in pymepix/etc/default.yaml contradict settings in pymepix/etc/auto_save.yaml user should be asked which one to load.

[jokuha]

Indeed

• which should use standard Python tools,
• be automatically saved and read at program end/start
• provide a GUI preferences dialog, which also allows to save and store explicit copies of such configurations