2 switch options for all graph-diagrams

[ennobaer]

Request for general Chart-Extension:
Can you implement two switching options for each original diagram, so that you don’t go to the
original values, but to the difference values. This example is about a gas meter with “state_class”:
“total_increasing”.

The 1st value at the time of February 2nd is 37449.31. All values shown are subtracted by 37449.31
beforehand.
And a third view (Chart 3) would be useful, where all values are displayed for each time unit, like
in the energy panel:
The currently displayed values are also subtracted from the 1st value (37449.31), but with each
subsequent value the previous value is subtracted.

All infos are in pdf-document german and englisch:
Homeassistant-Graph-Extension.pdf