flattened flann directory structure; patched zlib to build with Android NDK

3rdparty/zlib/gzguts.h

@@ -19,7 +19,7 @@
 #endif
 
 #include <stdio.h>
-#include "zlib.h"
+#include "zutil.h"
 #ifdef STDC
 #  include <string.h>
 #  include <stdlib.h>
@@ -36,6 +36,10 @@
 #  define vsnprintf _vsnprintf
 #endif
 
+#ifdef __GNUC__
+#include <unistd.h>
+#endif
+
 #ifndef local
 #  define local static
 #endif

3rdparty/zlib/zutil.h

@@ -21,6 +21,13 @@
 
 #include "zlib.h"
 
+#ifdef __arm__
+#  define z_off64_t z_off_t
+#endif
+#ifndef Z_TREES
+#define Z_TREES 6
+#endif
+
 #ifdef STDC
 #  if !(defined(_WIN32_WCE) && defined(_MSC_VER))
 #    include <stddef.h>