~ruther/nix-fpga

ref: 4731584fb847393fcf23c1dca9d7f6bc82c29240 nix-fpga/pkgs d---------
fix: ise udev
feat: add usb-driver to ISE
fix: ise udev
fix: update ISE udev rules
fix: require INSTALL_DIR only in final packages, not in shells
feat: add executables to fhs package, split to individual frameworks