Update version.h to v1.6.0

Author: ligenxxxx

src/version.h

@@ -2,7 +2,7 @@
 #define __VERSION_H_
 
 #define VTX_VERSION_MAJOR       1 // increment when a major release is made (big new feature, etc)
-#define VTX_VERSION_MINOR       5 // increment when a minor release is made (small new feature, change etc)
+#define VTX_VERSION_MINOR       6 // increment when a minor release is made (small new feature, change etc)
 #define VTX_VERSION_PATCH_LEVEL 0 // increment when a bug is fixed
 #define VTX_VERSION_STRING      STR(VTX_VERSION_MAJOR) "." STR(VTX_VERSION_MINOR) "." STR(VTX_VERSION_PATCH_LEVEL)