Transition hm_next to ruby 1.9.3

Bump hm_next to:
- use new eventmachine
- use fully qualifed constant names

git shortlog hm_next:

Bob Nugmanov and Maria Shaldibina (2):
  Refactor specs
  Bump eventmachine to 1.0.0

Change hm_next job spec to use ruby_next (1.9.3)

Change-Id: Iae13099051155290c5f73a7076fc3365d3be29a8