Don't add --color when --json is passed to rustc. fixes #488
Don't add --color when --json is passed to rustc. fixes #488

glandium/sccache,mozilla/sccache,glandium/sccache,mozilla/sccache,glandium/sccache,luser/sccache2,glandium/sccache,luser/sccache2,mozilla/sccache,luser/sccache2,luser/sccache2