Thrift-1286: Modernize the Thrift Ruby Library Dev Environment

Thrift-1286: Modernize the Thrift Ruby Library Dev Environment
Client: Ruby
Patch: jfarrell

Updates to ruby build process with the following changes:
 - Removes dependency on echoe for spec generation
 - Adds gemfile for bulider and uses thrift.gemspec for dependency management.
 - Adds checks in configure for builder and only calls if available (make check-local on ci servers)
 - Adds checks in configure for Ruby and rake (bundler as well but this is optional for check-local and auto dependency management)
 - Still allows for rake to do its thing if all dependencies are in place
 - Removed Manifest and setup.rb
 - Adds a install task which will generate a gem and then install that gem to locally configured ruby path (no more prefix or destdir with this client)

git-svn-id: https://svn.apache.org/repos/asf/thrift/trunk@1163341 13f79535-47bb-0310-9956-ffa450edef68