Dashboards

• Drive Tops: Added total average speed and of the last days driving
• All dashboards: Added dropdown menu to access all custom dashboards

Other changes

• Added option to dashboards.sh to automatically download and install latest release
• Updated screenshots
• Updated readme

Full Changelog: https://github.com/CarlosCuezva/dashboards-Grafana-Teslamate/compare/v1.15.1...v1.16.0