Derive Debug for many structs
Created by: azriel91
In order for PistonDevelopers/conrod#839 to have some full Debug implementations, this crate needs to be updated and released.
The PR build will fail until https://github.com/dylanede/stb_truetype-rs/pull/6 is merged and a new version published (I did an anticipatory dependency bump to version 0.2.2)