Add shortcuts for unsigned int, short, long and char

Feel free to use those in the new code.

And stay away from simple "unsigned".

source/blender/blenlib/BLI_sys_types.h

@@ -80,6 +80,11 @@ typedef uint64_t u_int64_t;
 #include <stddef.h>  /* size_t define */
 #include <stdbool.h>
 
+typedef unsigned int uint;
+typedef unsigned short ushort;
+typedef unsigned long ulong;
+typedef unsigned char uchar;
+
 #ifdef __cplusplus 
 }
 #endif