Broken example introduced

[cognalog]

Dear Airflow Maintainers,

Before I tell you about my issue, let me describe my environment:

Environment

• Version of Airflow (e.g. a release version, running your own fork, running off master -- provide a git log snippet): master branch, commit 4865ee6
• Screen shots of your DAG's graph and tree views:
• Stack trace if applicable:

[2016-04-06 19:19:09,361] {models.py:233} ERROR - Failed to import: /usr/local/lib/python2.7/dist-packages/airflow-1.7.0-py2.7.egg/airflow/example_dags/example_skip_dag.py
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/airflow-1.7.0-py2.7.egg/airflow/models.py", line 231, in process_file
    m = imp.load_source(mod_name, filepath)
  File "/usr/local/lib/python2.7/dist-packages/airflow-1.7.0-py2.7.egg/airflow/example_dags/example_skip_dag.py", line 60, in <module>
    create_test_pipeline('1', 'all_success', dag)
  File "/usr/local/lib/python2.7/dist-packages/airflow-1.7.0-py2.7.egg/airflow/example_dags/example_skip_dag.py", line 48, in create_test_pipeline
    op = MyEmrOperator(task_id='my_task_id', dag=dag,
NameError: global name 'MyEmrOperator' is not defined

• Operating System: (Windows Version or $ uname -a) Ubuntu 14.04
• Python Version: $ python --version 2.7.6

Description of Issue

• What did you expect to happen? All examples are loaded properly
• What happened instead? One example can't be loaded

Reproduction Steps

1. airflow webserver

@withnale, you may know what's going on?

[jlowin]

Sorry about that @ty707 -- an extra operator related to a discussion we were having offline snuck into the PR -- @r39132 fixed it in #1316 and I discovered that not all example dags are being unit tested, #1317.

[cognalog]

No sweat, glad some unit tests came out of it 😁

[withnale]

My bad. Sorry this got through. I fixed it an hour later in the PR branch when I noticed it, but it had been merged by them.