This fork of icotools is only here for the Quick and Dirty hack needed for adding icezero pcb to my Learn-Fpga fork. Will find a better solution if icezero port is adpoted into the main tree Learn-Fpga was forked from.
Get hold of WiringPi if it's not already installed and then do the following on your raspberry pi.
cd examples/icezero/
make icezprog
make icezprog-0x830000
make icezprog-0x1000000
Slightly more detailed notes here.