Add `bin/bench` to run the benchmarks from the top level
Add `bin/bench` to run the benchmarks from the top level

I usually keep my cwd in the top directory when working, and want a
shortcut for this

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