Little finetuning of example sketches

Just a little finetuning of the example sketches. There few redundant delays.

Improved the interrupt example sketch

Improved the interrupt example sketch:

• more comments to explain the thresholds
• automatic adjustment of the code for ESP32 and ESP8266

Other improvements:

• added VL6180xDefaultSettings() because VL6180xDefautSettings() was wrongly spelled. But still kept VL6180xDefautSettings for downward compatibility.

ChangeAddress method now working

The changeAdress method is now working.

Link to the english documentation changed

For some reasons I had to change the link to the english documentation of the library:

https://wolles-elektronikkiste.de/en/vl6180x-tof-proximity-and-ambient-light-sensor

No change to the code.

English documentation available

No change to source code. I have just translated my blog post, in which I describe the the VL6180X and the library.

keywords.txt added

keywords.txt has been added.

Another update of library.properties

Added "includes" to the library.properties

Library.Properties updated

Library.Properties updated

Compatibility issues with SAMD solved

• Compatibility issues with SAMD solved
• Some re-arrangements of the folder structure

Minor issue solved

corrected:

#ifndef VL6180X_WE_h_
#define VL6180X_WE_h_