Implement `Error` for our errors
Implement `Error` for our errors

What a concept! (Specifically looking at the usage crates.io would need
made it clear I had forgotten to do this)

SoftwareWarlock/diesel,mcasper/diesel,cascalheira/diesel,sgrif/diesel,sgrif/diesel,diesel-rs/diesel,diesel-rs/diesel,tohou/diesel,SoftwareWarlock/diesel,cascalheira/diesel,tohou/diesel,mcasper/diesel