This pull request attempts to fix some compiler warnings on Windows when compiled in Release mode.
```
"zlib-ng\ALL_BUILD.vcxproj" (default target) (1) ->
"zlib-ng\zlibstatic.vcxproj" (default target) (6) ->
zlib-ng\deflate.c(1626): warning C4244: '=': conversion from 'uint16_t' to 'unsigned cha
r', possible loss of data [zlib-ng\zlibstatic.vcxproj]
zlib-ng\deflate_fast.c(61): warning C4244: '=': conversion from 'uint16_t' to 'unsigned
char', possible loss of data [zlib-ng\zlibstatic.vcxproj]
zlib-ng\deflate_slow.c(89): warning C4244: '=': conversion from 'uint16_t' to 'unsigned
char', possible loss of data [zlib-ng\zlibstatic.vcxproj]
```
#else
# define _tr_tally_lit(s, c, flush) flush = _tr_tally(s, 0, c)
# define _tr_tally_dist(s, distance, length, flush) \
- flush = _tr_tally(s, distance, length)
+ flush = _tr_tally(s, (unsigned)(distance), (unsigned)(length))
#endif
/* ===========================================================================