* foundation: Remove unused ucp.h
Nothing use this and it is not even included in Visual Studio project
files. Remove it so it will not confuse any more.
* foundation: Hide zlib from user
Hide zlib completly from user. This way we do not need to publish zlib.h
or zconfig.h.
As we now have two different pointer initalizing in constructor I choose
to use unique pointers so it is more obvious those are safe. I also
choose to use make_unique which default initalize z_stream_t. This makes
code more readable as we do not need to specifie every field of
z_stream_t. It really should not matter much if we initialize couple
field for nothing. If does we should add comment about that. Still
keeping _buffer without inializing as it is quite big.
* xml: Hide expat and ParserEngine from user
Hide expat completly from user. This way we do not need to publish
expat.h or expat_external.h.
I move also headers to orignal locations so diff is smaller compared to
original.
* chore(Foundation): Compression level constants
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Co-authored-by: Kari Argillander <kari.argillander@fidelix.com>