Mandelbrot Discovery needs config-parser

[ckormanyos]

Implement a simple config-parser for Mandelbrot Discovery in order to load images. Could/should this also support JPEG rescaling to the native $768{\times}768$ pixels of the discovery program?

[ckormanyos]

Also create (in addition to a config-import) a config-export mechanism.

[ckormanyos]

The preliminary architecture is cycling in #187, but there is still a lot to do. I'll push that to master just to have an architectural placeholder.