fix #136 - Error: cannot implicitly convert expression ~this.registry…

… of type const(ulong) to immutable(uint)

src/containers/unrolledlist.d

@@ -565,7 +565,7 @@ private:
 			static if (BookkeepingType.sizeof < uint.sizeof)
 				immutable uint notReg = ~(cast(uint) registry);
 			else
-				immutable uint notReg = ~registry;
+				immutable uint notReg = cast(uint) (~registry);
 			version (LDC)
 			{
 				import ldc.intrinsics : llvm_cttz;