Consolidation of Wemos.ino and WifiShield.ino

[dl1com]

Depending on the controller hardware, the user has to choose between Wemos.ino and WifiShield.ino in the /examples folder.
Although they take care of special prerequisites caused by the different hardware, large parts of the code are pretty similar.
To avoid the necessity of fixing bug or introducing a feature in two separate *.ino files, it should be evaluated how far these projects could be merged into a single sketch.

[thgeorgiou]

This is a good idea, we can use #ifdef to redefine the function that sends data for the ESP8266 since that's the main difference.