Bump jruby version to 1.7.2.
Bump jruby version to 1.7.2.

eunomie/chgo,JeanMertz/chruby-fish,eunomie/chgo,rstacruz/chruby-fish,ngpestelos/chruby,regularfry/chruby,ngpestelos/chruby,ilikepi/chruby,regularfry/chruby,postmodern/chruby,postmodern/chruby,kbrock/chruby,JeanMertz/chruby-fish,kbrock/chruby,rstacruz/chruby-fish,ilikepi/chruby