Merge branch 'signal' of https://github.com/dlrobertson/relibc into dlrobertson-signal

Cargo.lock

Cargo.toml

include/bits/signal.h

include/bits/timespec.h

src/fcntl/cbindgen.toml

src/signal/Cargo.toml

src/signal/build.rs

src/signal/cbindgen.toml

src/signal/src/lib.rs

src/signal/src/linux.rs

src/signal/src/redox.rs