MDEV-9024 Build fails with VS2015

Fix build failures caused by new C runtime library
- isnan, snprintf, struct timespec are now defined, attempt to
redefine them leads
- P_tmpdir, tzname are no more defined
-  lfind() and lsearch() in lf_hash.c had to be renamed,  declaration
conflicts with some C runtime functions with the same name declared in
a header included by stdlib.h

 Also fix couple of annoying warnings :
- remove #define NOMINMAX from config.h to avoid "redefined" compiler
warnings(NOMINMAX is already in compile flags)

- disable incremental linker in Debug as well (feature not used much
and compiler crashes often)


Also simplify package building with Wix, require Wix 3.9 or later
(VS2015 is not compatible with old Wix 3.5/3.6)

include/my_pthread.h

@@ -86,10 +86,12 @@ typedef volatile LONG my_pthread_once_t;
 #define MY_PTHREAD_ONCE_INPROGRESS 1
 #define MY_PTHREAD_ONCE_DONE 2
 
+#if !STRUCT_TIMESPEC_HAS_TV_SEC  || !STRUCT_TIMESPEC_HAS_TV_NSEC
 struct timespec {
   time_t tv_sec;
   long tv_nsec;
 };
+#endif
 
 int win_pthread_mutex_trylock(pthread_mutex_t *mutex);
 int pthread_create(pthread_t *, const pthread_attr_t *, pthread_handler, void *);