[lametrictime] Move external library to internal code

[kaikreuzer]

See #14165 (comment)

Remarks:

• I moved @syphr42 library code to src/main/java (and src/test/java for tests).
• I couldn't remove src/3rdparty/java, since there are still some external CDDL classes left.
• The CDDL classes do not have openHAB license header, so they won't be an issue for license:format.
• I addressed all SAT errors like missing Javadoc headers and author tags.
• I didn't address SAT warnings wrt null annotations as a lot of code are pojos that do not really benefit from it and which would have meant significant effort.

[jlaur]

• I didn't address SAT warnings wrt null annotations as a lot of code are pojos that do not really benefit from it and which would have meant significant effort.

The POJOs could be moved to a folder with the name dto, in which case SAT will not complain about missing null annotations.

[mhilbush]

The POJOs could be moved to a folder with the name dto

Yep, for SleepIQ, I just renamed the model directory to dto.

[kaikreuzer]

Thanks, that's a good hint, I didn't know this feature yet!
I've moved the model classes and added null annotations to all other classes now.

[jlaur]

I've moved the model classes and added null annotations to all other classes now.

Awesome, thanks for the effort put into this @kaikreuzer.

[jlaur]

LGTM