rb: Use File.dirname(__FILE__) in generated requires [THRIFT-57]

This means you no longer have to put the gen-rb folder in $:

Author: Kevin Ballard <kevin@rapleaf.com>


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@671963 13f79535-47bb-0310-9956-ffa450edef68
10 files changed