A modification of Waninkoko's WAD Manager for the Wii, it includes many extra features such as (un)installation of multiple WADs at the same time and support for Hermes cIOS v4/v5, see the included "readme" file for a full set of features.
I don't have a wii u anymore to test it myself, but if homebrews are not visible on the wii u menu I think you can press L + R + minus to open the plugin menu, there should be an option called "homebrews on wii u menu" or something similar