Module "uzlib" - based on similarly named library

Comparing to miniz- based modzlibd:

~~~~
   3474	      0	      0	   3474	    d92	build/extmod/moduzlib.o
   6482	      0	      0	   6482	   1952	build/extmod/modzlibd.o
~~~~

Runtime memory usage (for decompresser object) is ~1.2K vs ~5K (IIRC). And of course, uzlib will allow us to implement compression support - later, need uzlib API refactoring to support Python-compatible interface.