Jhbate/add platform

initial PR that includes the now uses the platform client

- added travis build
- extract interaction with the tidepool platform into api and use the platform client
- log errors to the tidepool platform for diagnostics
I like the idea of a mock API, but you don't seem to be using it yet? Plus, it doesn't look like it matches the "real" API, the function signatures aren't the same... Maybe it's best to leave it out until we actually use it? I worry that it might be confusing otherwise...