Large refactor to limit dependencies on the backend service.
- Renamed backend service to message-middleware.
- Moved communication with the message-middleware into the input-list directive.
- Refactored the midi-input directive to broadcast changes instead of updating the message-middleware directly.
- Refactored the osc-output directive to broadcast changes instead of updating the message-middleware directly.
- Refactored the osc-output directive to separate input parameter list in the DOM from the input parameter list in the inputConfig.
- Refactored the inputConfig to validate input configuration that will eventually come from external sources.
- Refactored the inputConfig to communicate config changes with the message-middleware.
- Replaced console.log calls with $log calls.
Merge branch 'develop' of https://github.com/OSCModulator/oscmodulator into feature/cleanup-todos