Add rumprun CI and get tests passing

.travis.yml

ci/rumprun/Dockerfile

ci/run-travis.sh

ci/run.sh

libc-test/build.rs

src/lib.rs

src/macros.rs

src/unix/bsd/apple/mod.rs

src/unix/bsd/freebsdlike/mod.rs

src/unix/bsd/mod.rs

src/unix/bsd/openbsdlike/bitrig.rs

src/unix/bsd/openbsdlike/mod.rs

src/unix/bsd/openbsdlike/netbsd.rs

src/unix/bsd/openbsdlike/openbsd.rs

src/unix/mod.rs

src/unix/notbsd/mod.rs