Support for ESP32-CAM modules

[excieve]

Although Ai-Thinker ESP32-CAM module and the clones can work with the generic esp32 environment, there are some specifics different from the esp32doit-devkit-v1 board configuration used in it.

With this change OTA actually works fine through the following changes:

• board configuration set to esp32cam
• partitions spec set to min_spiffs.csv, which allows for OTA partitions to be set up on the image (unlike the default one)
• ArduinoOTA timeout changed from the default 1s to 3s — I found that otherwise it bails out too often before completing, especially if the wireless connection isn't ideal

Additionally, this adds a helpful WiFi status indication through the on-board red LED present on those modules at pin 33. When set to LOW it will turn on and it will turn off when set to HIGH.

[henrykuijpers]

@excieve What would the esp32-cam add to the ESPAltherma? Is there something specific that needs to be photographed on the heatpump or anything? (Just trying to understand the usecase for the camera)