Sun Jan 19 20:56:15 CET 2014

SP structures

It seems best to stick to the sp structures as default.  Leave the
static C interfaces for where it makes sense, i.e. on deeply embedded

To make this work, make it possible to share the functionality in

- librai.c  -> operate on a (linked) rai_info
- sp.c      -> load binary .sp into rai_info 
(+- done: rai.c rai_sp.c)