feat(epicardium): read card10.cfg

Adds simple config parser along with config_ API that:

• supports default values for options
• allows typed querying of config values
• types supported: boolean, integer, floating point and string

unknown options are ignored and LOG_WARNed on the console

So it seems I suck at writing parsers, the main loop is a little wonky but it works.

Tested:

• int, bool, double option types
• option.names.with.dots
• whitespace all over the place
• empty card10.cfg