Auto merge of #756 - matthiasbeyer:fix-readme, r=kbknapp
Auto merge of #756 - matthiasbeyer:fix-readme, r=kbknapp

Fix typo: 2.12.0 -> 1.12.0

Fixing a typo here.

clap-rs/clap,kbknapp/clap-rs,clap-rs/clap,clap-rs/clap,kbknapp/clap-rs