Set up TravisCI, codecov

[JohnStrunk]

Describe the feature you'd like to have. Each commit/PR should be checked via Travis.

• Run linters
• Run unit tests

What is the value to the end user? (why is it a priority?) Having linting and unit tests provide a minimum level of assurance for new code submissions, helping to keep quality high.

How will we know we have a good solution? (acceptance criteria) Each Commit and PR should be checked:

• linting of all code and docs (if it's a structured file, we should lint it)
• Run all unit tests
• Integrate w/ codecov to ensure coverage of unit tests remains acceptable

Additional context Child of #5

[JohnStrunk]

Moving this back to the backlog to be picked up again once we have code.