Add --yes as alias for -y
Add --yes as alias for -y

This should fix #557.

Boddlnagg/rustup.rs,Boddlnagg/rustup.rs,theindigamer/rustup.rs,rust-lang/rustup,rust-lang/rustup,polonez/rustup.rs,polonez/rustup.rs,rust-lang/rustup,theindigamer/rustup.rs,polonez/rustup.rs,polonez/rustup.rs,nodakai/rustup.rs,Boddlnagg/rustup.rs,nodakai/rustup.rs,Boddlnagg/rustup.rs,theindigamer/rustup.rs,inejge/rustup.rs,nodakai/rustup.rs,theindigamer/rustup.rs,inejge/rustup.rs,polonez/rustup.rs,rust-lang/rustup,theindigamer/rustup.rs,nodakai/rustup.rs,rust-lang/rustup,inejge/rustup.rs,Boddlnagg/rustup.rs,nodakai/rustup.rs,inejge/rustup.rs,inejge/rustup.rs