Auto merge of #4701 - mathstuf:update-lockfile-color-reflects-change, r=alexcrichton
Auto merge of #4701 - mathstuf:update-lockfile-color-reflects-change, r=alexcrichton

cargo_generate_lockfile: use color to also indicate the change

In English, `Updating` and `Removing` are the same length and scanning
the list for changes is hard. Use color to help indicate the kind of
change that is occurring.

vojtechkral/cargo,eminence/cargo,rustyhorde/cargo,eminence/cargo,vojtechkral/cargo,tsurai/cargo,rust-lang/cargo,tshepang/cargo,nipunn1313/cargo,achanda/cargo,achanda/cargo,achanda/cargo,achanda/cargo,tsurai/cargo,eminence/cargo,tshepang/cargo,tshepang/cargo,tshepang/cargo,rust-lang/cargo,rustyhorde/cargo,tsurai/cargo,nipunn1313/cargo,vojtechkral/cargo,tsurai/cargo,rust-lang/cargo,rustyhorde/cargo,eminence/cargo,nipunn1313/cargo,tsurai/cargo,rustyhorde/cargo,nipunn1313/cargo,rust-lang/cargo,vojtechkral/cargo