implement yaml configuration

[nicb]

A configuration should be implemented for:

• x_size
• y_size
• x_range
• y_range

and it should also be overridden by a configuration file read on the fly from command arg option -c.

[nicb]

Or maybe a better idea would be to provide a frame command in the DSL to provide all options (which should have defaults). Again:

• ranges
• sizes
• log/lin
• grid on/off
• ...