Add example project to showcase sparrow

[jonas]

Motivation

Provide an example which covers a simple case but which still gives a good introduction on how to use sparrow. The example project can also serve as an integration test.

Input

• Published artifacts (issue Publish build artifacts to bintray #8)
• Sample data TBD, for example http://donnees.ville.montreal.qc.ca/

Output

• Example code using @schema macro with @embedded case classes
• Integration tests for example code

Test

• CI passes