Merge branch 'cstr' into 'master'

Cargo.lock

Cargo.toml

src/c_str.rs

src/db.rs

src/fs.rs

src/header/dlfcn/mod.rs

src/header/grp/mod.rs

src/header/netdb/host.rs

src/header/netdb/linux.rs

src/header/netdb/mod.rs

src/header/netdb/redox.rs

src/header/stdio/default.rs

src/header/stdio/mod.rs

src/header/stdlib/mod.rs

src/ld_so/dso.rs

src/ld_so/linker.rs

src/lib.rs

src/platform/linux/mod.rs

src/platform/pal/mod.rs

src/platform/redox/exec.rs