Add driver framework

[furesoft]

add driver framework to load drivers from files

[EdNutting]

Hi furesoft,
There are currently two processes to enable this. Firstly, the file system managers exist to enable reading from HDD/USB. Secondly, old code (that needs updating) is available for loading statically-linked (and a limited form of dynamically linked IIRC) ELF-based executables. Combining these would allow loading drivers from files.

Unfortunately I don't actively maintain FlingOS at the moment, but if you fancy giving this a go and creating a PR I'd be happy to accept it.

Best regards,
Ed