Update cmd2 to 0.7.0

[pyup-bot]

There's a new version of cmd2 available.
You are currently using 0.6.7. I have updated it to 0.7.0

These links might come in handy: PyPI | Changelog | Repo | Docs

Changelog

0.7.0

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Release date: 2017-02-23

• Refactored to use six module for a unified codebase which supports both Python 2 and Python 3
• Stabilized on all platforms (Windows, Mac, Linux) and all supported Python versions (2.7, 3.3, 3.4, 3.5, 3.6, PyPy)
• Added lots of unit tests and fixed a number of bugs
• Improved documentation and moved it to cmd2.readthedocs.io

0.6.9

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Release date: 2016-10-03

• Support Python 3 input()
• Fix subprocess.mswindows bug
• Add Python3.6 support
• Drop distutils from setup.py

0.6.8

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Release date: 2014-12-09

• better editor checking (by Ian Cordascu)

Got merge conflicts? Close this PR and delete the branch. I'll create a new PR for you.

Happy merging! 🤖