Added benchmarks for chruby_use.
Added benchmarks for chruby_use.

ngpestelos/chruby,ngpestelos/chruby,kbrock/chruby,regularfry/chruby,postmodern/chruby,ilikepi/chruby,ilikepi/chruby,regularfry/chruby,kbrock/chruby,postmodern/chruby,eunomie/chgo,eunomie/chgo