v0.4.4: Expose raw allergy risk value and refactor allergy risk forecasts

Changes

• #18 Add sensor scale documentation @krissen
• #19 Update README with description of allergen level scale @krissen

🚀 Features

• #23 Expose unscaled allergy risk value @krissen
• #29 Expose raw value for allergy risk and refactor allergy risk forecast @krissen

🐛 Bug Fixes

• #21 Changed user-facing string 'United Kingdom' to 'Great Britain' @krissen
• #24 Use named state for allergy risk sensor @krissen
• #25 Fix forecast format for allergy risk sensor @krissen
• #26 Add raw allergy risk values for hourly sensor @krissen
• #27 Normalize allergy risk forecast structure @krissen
• #28 Handle outdated sensors in polleninformation integration @krissen
• #29 Expose raw value for allergy risk and refactor allergy risk forecast @krissen

Full Changelog: v0.4.3...v0.4.4