Refactor FileHeartManMock
Add #createRandomDevice() on HeartManSimulator

This lets you create a HeartManDevice which sends random data. Useful
for testing purposes.
Search for services in HeartManDiscovery#discoverHeartManDevices()

This is needed so it's possible to start listening on a device while we
are already listening on another one.
Remove BytePlayer and deprecated ByteConverter

This closes #2
Merge pull request #6 from pangratz/refactor

Refactor all the things!