Rust backwards compatibility

The time crate breakage was an unusually awful failure, and we're working on several process and language improvements to make sure it doesn't happen in the future. (Short version: a case where only one possible type could be the answer became a case where more than one could be, causing a type inference failure, and we're working on proactively catching and avoiding cases like that.)

That said, one huge advantage of the FreeBSD way of doing things over most other software distributions is that they have all the code in one place and can patch all software in the same commit that upgrades tools.