1.1.0

• errors2.rs: update link to Rust book (#124)
• Start verification at most recently modified file (#120)
• Watch for file creation events in watch mode (#117)
• Add standard library types to exercises suite (#119)
• Give a warning when Rustlings isn't run from the right directory (#123)
• Verify that rust version is recent enough to install Rustlings (#131)

If you have Rustlings cloned, you can upgrade like so:

git fetch
git checkout tags/1.1.0