Add UTC EpochTime function

[heumann-a]

Add functionality to get raw UTC time without Offset for DST calculations

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[github-actions[bot]]

Memory usage change @ 0708c65bb058b6690ba5c81ca0420c41aca8f20e

Board	flash	%	RAM for global variables	%
esp8266:esp8266:huzzah	N/A	N/A	N/A	N/A

Click for full report table

Board	examples/Advanced flash	%	examples/Advanced RAM for global variables	%	examples/Basic flash	%	examples/Basic RAM for global variables	%	examples/IsTimeSet flash	%	examples/IsTimeSet RAM for global variables	%
esp8266:esp8266:huzzah	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A	N/A

Click for full report CSV

Board,examples/Advanced<br>flash,%,examples/Advanced<br>RAM for global variables,%,examples/Basic<br>flash,%,examples/Basic<br>RAM for global variables,%,examples/IsTimeSet<br>flash,%,examples/IsTimeSet<br>RAM for global variables,%
esp8266:esp8266:huzzah,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A,N/A