Took out unecessary code

Since the main.c comes from another project, much of its original code
wasn’t needed
Deleted unnecessary archives and added the packet format
Added SPI interface files

Added SPI interface files and included the appropriate headers in main.c
Removed old SPI and added new

Removed old SPI library in favour of a new one that supports interrupt
driven transfers
Removed unnecessary files from SPI lib
Starting to port the RF22 code

Changed function names, variable names, etc.
More changes to old code...
Clock frequency and syntax beautification
Datagram additions

* Changed datagram functions for classless operation
* Moved constructor stuff into init function
* As usual, changing class variables to globals (g_ prefix)