Merge pull request #760 from redox-os/chroot

drivers/vesad/src/display.rs

kernel/lib.rs

kernel/scheme/user.rs

kernel/syscall/fs.rs

kernel/syscall/mod.rs

kernel/syscall/process.rs

libstd/libc/src/syscall.rs

programs/contain/src/chroot.rs

programs/contain/src/main.rs

rust

schemes/redoxfs

syscall