Update specs with transcode

Unlock RSpec in Gemspec
Temporarily remove Gemfile.lock
Update specs with transcode
Disable screenshots (RSpec)
RSpec 2.14.1 Compatible

Restore screenshots in spec_helper.rb
Example.exception and description handling are now compatible
with RSpec 3.0.0.beta2.
Clean up after(:each) (RSpec)
Add Gemfile.lock (RSpec 2.14.1)
Update version info, 1.13.3