Updated unit tests for ruby 2.0

This diff adds support for using ruby 2.0 in the test suite by
disabling the S3CommandsTest since the aws/s3 gem in rubygems doesn't
support ruby 2.0 yet.  I also updated the Gemfile.lock to have newer
versions.  RightAWS now contains more tests to tickle execution paths
that were hit in S3CommandsTest.