gateware.boneless: use explicit SRU datapath (-16 DFFESR, +16 DFFSR, +1 LUT). Before: Number of cells: 627 SB_CARRY 77 SB_DFF 1 SB_DFFE 1 SB_DFFESR 80 SB_DFFSR 19 SB_LUT4 448 SB_RAM40_4K 1 After: Number of cells: 628 SB_CARRY 77 SB_DFF 1 SB_DFFE 1 SB_DFFESR 64 SB_DFFSR 35 SB_LUT4 449 SB_RAM40_4K 1

gateware.boneless: use explicit ALU datapath (-16 CARRY, -11 LUT). Before: Number of cells: 654 SB_CARRY 93 SB_DFF 1 SB_DFFE 1 SB_DFFESR 80 SB_DFFSR 19 SB_LUT4 459 SB_RAM40_4K 1 After: Number of cells: 627 SB_CARRY 77 SB_DFF 1 SB_DFFE 1 SB_DFFESR 80 SB_DFFSR 19 SB_LUT4 448 SB_RAM40_4K 1

arch.boneless: fix typo.

arch.boneless: fix instruction set summary.

arch.boneless: rename O flag to V flag. To avoid confusion with zero.

arch.boneless: unswap CMP operands, actually make flags work properly. Huge thanks to @cr1901 for figuring out all the necessary bit twiddling.

gateware.boneless: oops, accidentally swapped operands of SUB and CMP.

arch.boneless: add missing exports.

Travis: migen should be installed by setuptools already.

software: build libfx2 in `python setup.py build_ext` too.