* Added the configuration for the second generation OBI devices.

* Added link to the OBI Wifi Schuko Plug V2 as well as included the device in the readme.

* Restored the default configuration accidentially changed by a previous commit.

* Renamed the OBI-V2 device to EUROMATE_WIFI_STECKER_SCHUKO_V2 as suggested by mcspr.

* Fixed spelling of comment to the proper wording Schuko.

Do not change the default env

It seems to be very similar to the ITead Sonoff B1, so it's based on that.

* Works with many different ultrasonic sensor models: HC-SR04, SRF05,
  SRF06, DYP-ME007, JSN-SR04T & Parallax PING)))™.
* Built-in digital filter method ping_median() for easy error correction
  (use SONAR_ITERATIONS build flag to configure).
* Allows setting of a maximum distance where pings beyond that distance
  are read as no ping or clear (use SONAR_MAX_DISTANCE build flag).