This addon code is now merge into Blender 2.8 repository, via official glTF 2.0 Blender IO addon from KhronosGroup.
If you are using Blender 2.8, addon is activated by default, you don't need to install or activate anything.
If you are using Blender 2.79, please install official glTF 2.0 Blender IO addon from KhronosGroup.
(These glTF files are from glTF samples)
This development is done in strong collaboration with Airbus Defence & Space