Release candidate for internal changes

Release Notes:

1. The "yesterdays rates" functionality now refreshes from the API rather than the locally cached data. This is more robust if the process inadvertently runs twice in a day and newly created devices will have this data available immediately

2. Simplified and cleaned up the overly complex conditional logic that evolved rather than being designed and resulted in lack of clarity. improved readability and comments in the code to assist this

Note: The "Yesterday_Standing_Charge" state is set at todays rate on the initial device refresh after creations. this is because the API does not publish historical standing charge. This is a design choice as the only situation where this could be inaccurate is if the rate changed the day before the device was created. In that case it will be accurate moving forward, and that is better than having a default hard coded. The impact even if it happened should be minor, and it is better than under reporting it to zero.