Allow to select Cargo features when building/debugging

At first, this can be a [`StringListPropery`](https://msdn.microsoft.com/en-us/library/microsoft.build.framework.xamltypes.stringlistproperty.aspx) in `ConfigurationGeneral` (Rules\General.xaml). Later, there could be some UI that shows all available features defined in the manifest and allows to select them with checkmarks.
