Implement a dummy sgtty

Cargo.lock

Cargo.toml

src/lib.rs

src/sgtty/Cargo.toml

src/sgtty/build.rs

src/sgtty/cbindgen.toml

src/sgtty/src/lib.rs

src/sys_ioctl/Cargo.toml

src/sys_ioctl/cbindgen.toml

src/sys_ioctl/src/lib.rs

src/sys_wait/cbindgen.toml