Support searching instances by type specific properties

[Toxantron]

Is your feature request related to a problem? Please describe.
In PHOENIXCONTACT/MORYX-AbstractionLayer#146 we addes support to load instances by the standard properties Type, TypeId, TypeName or TypeIdentity. It would by great to load all instances with type specific properties. For example:

// Load instances of all types with a weight below 500g
var watches = ProductManagement.LoadInstances<WatchInstance>(wi => wi.Type.Weight < 500);

Describe alternatives you've considered
Use the new type expression to load types and than all instances of those types.