This MR implements multiple things
- Add `.vscode/` to .gitignore
- Any files generated by Visual Studio code or its extensions will not be pushed.
- Give `InitialStartModule` a required `name` property
- Every `InitialStartModule` now requires a `name` property. This replaces the previous setup where a `property string name` was needed in the `contentitem` of the `InitialStartModule`.
- Remove the cellular page if no modem
- If the device has no modem (`PlasmaMM.SignalIndicator.modemAvailable == false`), the cellular page will no longer be shown.
Currently modules are initialized as QQuickItems. In order to be able to
add custom properties for modules to set in the future, introduce
InitialStartModule as the top-level QML object for modules to
initialize.
Currently only two properties are implemented: `available` for whether
to show the module in the wizard, and `contentItem` for the visual
module item.
