Fix Invalid Auth, plus new sensors
Thanks to the efforts of @ColinRobbins , @totalitarian and @Lee-BS-AMS, many issues have been closed:
- The documentation and issue links have been fixed (#37 closes #27)
- Cost and tariff sensors have been added (#46 closes #31 and #24)
- The integration now correctly handles invalid authentication (#46 closes #43 and #14)
- BST is no longer hardcoded (#46)
- Cumulative sensors have been added (#49 closes #25 and #45)
As well as this, Home Assistant 2021.10.01 supports using kWh in the gas section of energy management, so using m3 is no longer required 🎉