README grammar fix (#3926)
README grammar fix (#3926)

Remove comma splice
rust-lang/rustfmt,aidancully/rust,aidancully/rust,graydon/rust,graydon/rust,graydon/rust,SingingTree/rustfmt,graydon/rust,aidancully/rust,SingingTree/rustfmt,rust-lang/rustfmt,graydon/rust,graydon/rust,aidancully/rust,aidancully/rust,aidancully/rust