Add support for configuration of timestamp extractor

[willyborankin]

Add timestamp.resolution property to config timestamp extractor
There are two configuration parameter values:

• milliseconds - extracts timestamp from the field or the key and puts it as is in milliseconds
• seconds - extracts timestamp in seconds put in it in milliseconds

[HelenMel]

@willyborankin left couple comments

[ivanyu]

a couple of comments

[willyborankin]

@ivanyu and @HelenMel comments fixed

[ivanyu]

So, effectively we need this set of tests:

• Struct + value is Long + resolution is seconds;
• Map + value is Long + resolution is seconds;
• Struct + value is Long + resolution is milliseconds;
• Map + value is Long + resolution is milliseconds.

Some conversion according to the resolution should be done here.

Also:

• Struct + value is Date + resolution is seconds and milliseconds;
• Map + value is Date + resolution is seconds and milliseconds.

No conversion must be done here. Exactly the moment of time that is on the input should be on the output, despite the resolution setting.

There might be some way to use @ParametrizedTest to not copy too much code around.

[willyborankin]

@ivanyu all done

[ivanyu]

A couple of small changes, but overall LGTM

[willyborankin]

@ivanyu squashed