Add function to initialize time change point member variables.

Add constructor for time zones that do not observe daylight time.

Update example sketch.

Update example sketches:

Fix compiler warnings,
Button library name change,
Shorter code for function to print date and time.

GNU GPL v3.0.

Closes JChristensen#31.

Add CONTRIBUTING.md back.

Move source files to /src.

Closes JChristensen#7. Closes JChristensen#8. Closes JChristensen#11.  Closes JChristensen#14. Closes JChristensen#20. Closes JChristensen#24.

Fix under-allocated character array in WorldClock example. Closes JCh…

…ristensen#13.

Version 1.0

Alpha version, more testing needed.