FPGA place and route tool for Lattice iCE40 - with GUI

 nextpnr aims to be a vendor neutral, timing driven, FOSS FPGA place and route
 tool.
 .
 nextpnr-ice40 is to be used for Lattice iCE40 FPGAs and uses fpga-icestorm to
 achieve that.
 .
 This package can perform place-and-route for Lattice iCE40 devices
 and includes the QT GUI.