feat(api): use uintptr_t instead of intptr_t for pointers (#265)

Image methods now accept the `long` type instead of `int`,
as they are expected to work with pointers as well.

imgui-binding/src/generated/java/imgui/ImGuiKeyData.java

@@ -26,7 +26,7 @@ public final class ImGuiKeyData extends ImGuiStructDestroyable {
      */
 
     private native long nCreate(); /*
-        return (intptr_t)(new ImGuiKeyData());
+        return (uintptr_t)(new ImGuiKeyData());
     */
 
     /**