Added receive code and support for Webgear encapsulation.
More debugging macros/functions.
conditionalised timeout for start/join network
conditonalised attribute/common memory hacks
identified tracking code with XXX_TRACK
sorted out initialistion of instance structure to some extent
finished docuementing the start/join sequence
The code doesn't compile (I'll do that in a minute), but functionally
it gets to receveing the interrupt from the start or join net command.
There is a lot of code to deal with the limitations of the PCCard memory
mapping code - I'm changing some of it hence the check in to preserve something
that worked.