Carbon footprint tracking, Plan stability improvements

What's Changed

Added tracking of (UK initially) Carbon footprint

Requires HA integration: https://github.com/jfparis/sensor.carbon_intensity_uk and update to apps.yaml

  # Carbon Intensity data from National grid 
  carbon_intensity: 're:(sensor.carbon_intensity_uk)'

The carbon footprint can then be enabled with switch.predbat_carbon_enable and will be visible in the HTML plan card and also can be charted with Apex Charts (see the updated template for a carbon chart)

• Initial code @springfall2008 in #986
• Tidy html plan with carbon option a bit, better fit to mobile by @springfall2008 in #989
• Report carbon today by @springfall2008 in #993
• Update example_chart.yml to add carbon chart by @springfall2008 in #994
• Fix unit typo by @springfall2008 in #995

Changes to improve plan stability and avoid spurious hold charges at high rates:

• Adding Load divergence modelling by @springfall2008 in #984
  • Your load prediction will be modulated on a minute basis based on the standard deviation of the prediction in the next 4 hurs
• Fix for rounding issue with battery cycle by @springfall2008 in #983
• Changed weighting of charge vs no charging @springfall2008 in #990
  • Attempt to avoid hold charging when not required
• Align plan calculation to 5 minutes periods to improve stability
  • Attempt to avoid the plan changing quite often

Misc changes

• Moved Template dashboard to /addon_config/xxx area
• Added extra debug file creation (when debug_enable is on) @springfall2008 in #992

Full log

Full Changelog: v7.16.17...v7.17.0