* Erase all flash for USB uploads on ESP8266s
Previously, only erased "write regions".
Downside: Config for other FWs like tasmota could be affected
Upside: Potentially fixes some ESP8266 connection issues
Related: https://github.com/esphome/issues/issues/455#issuecomment-503524479
* Clear WiFi settings for ESP8266
Clears wifi settings from retained storage on ESP8266 (if set).
Unsure if this is the actual issue, but it won't cause problems either.
* Update wifi_component_esp8266.cpp
* Revert erase chip for testing
* Improve wait_time calculation
Otto Winter