Show version on web page

[marcoraddatz]

I updated the firmware via OTA and wasn't sure whether it was successful or not. Unfortunately, there's no version indicator on the start page or next to the OTA area.

It might be useful to show the currently installed version(s), so that users don't need to search the logs or do some proper monitoring.

[adlerre]

I add the version information to the info page.

BTW: The current version is also displayed on the device info card in Home Assistant.