When executing 'behave' cell magic in a notebook, behave prints output
to standard out. (http://behave.readthedocs.io/en/latest/tutorial.html)

Example output:
"""
    Feature: showing off behave # features/tutorial.feature:1

      Scenario: run a simple test        # features/tutorial.feature:3
        Given we have behave installed   # features/steps/tutorial.py:3
        When we implement a test         # features/steps/tutorial.py:7
        Then behave will test it for us! # features/steps/tutorial.py:11

    1 feature passed, 0 failed, 0 skipped
    1 scenario passed, 0 failed, 0 skipped
    3 steps passed, 0 failed, 0 skipped, 0 undefined
"""

Issue:
    Even when no hide checkbox is selected, I don't see standard output back in the html file.

Fix:
    I have added a Jinja elif for json key output.text; it just shows everything inside the json value.

Perhaps the filter logic could be better, but I am not that familiar with notebook output options.
IE; are data and text mutually exclusive?
Or are there even more types, which might warrant an {%- else -%}{{super()}}?