Add exporter to the API of a Piecewise instance

[critzo]

Our two data collection products, Piecewise and Murakami, should be able to work together.

• Piecewise instances can collect tests and surveys through a website as a public engagement tool.
• Murakami beacons can automatically run tests from a premise device
• Piecewise's API currently only works with a logged in user session, but it is planned to add API key support for using the Piecewise API with external applications.

Add an exporter to Murakami that uses the future Piecewise API key to post test results to a Piecewise instance.

This will enable data collection initiatives to use both a public engagement website and survey, and additionally deploy Murakami beacons to run regular tests and submit them into a Piecewise instance.