Remove MRI 1.9.2 from travis.yml.
Remove MRI 1.9.2 from travis.yml.

There is a problem with MiniTest::Mock in ruby 1.9.2 when mocking
special methods names such as 'send', 'hash', etc.

This fails in ruby 1.9.2: MiniTest::Mock.new.expect(:send, true)

Juanmcuello/garufa