0.5.0

• Don't require @clk and @reset ports in comb components
• inline pass supports inlining ref cells
• comb-prop: disable rewrite from wire.in = port when the output of a wire is read.
• BREAKING: Remove PortDef::into() because it makes it easy to miss copying attributes.
• Remove the futil binary.
• The calyx binary ships all the primitives and therefore self-contained now.
  • Add the calyx-stdlib package
  • Add a new build script that installs primitives when the package is installed.