Grid3D plugin does not find its QML file

[Thodoris1999]

Environment

Ubuntu 20.04, source installation

Description

Related to gazebosim/gz-rviz#82

In #324 Grid3D was merged with GridConfig and the Grid3D shared library was simply installed as an alias for GridConfig to maintain backwards compatibility. However, it Qt resources are not added and the plugin fails to load.

We can install the required files to fix this, but I don't mind removing the plugin and simply changing my ignition::gui::App()->LoadPlugin("Grid3D") to GridConfig.

Steps to reproduce

ign gui -s Grid3D
or run ign_rviz and add a Grid display.

Output

[GUI] [Err] [Plugin.cc:132] Can't find [:/Grid3D/Grid3D.qml]. Are you sure it was added to the .qrc file?