Add `zig-out` directory for the Zig programming language (#394)
Add `zig-out` directory for the Zig programming language (#394)

An update to the Zig programming language compiler changed the behaviour of the
`LibExeObjStep.install`  command to generate the resulting files in a `zig-out` directory
instead of the old `zig-cache/bin` directory.
dvcs/gitignore