Extend Base.propertynames and Base.hasproperty for ABMs to allow tab-autocomplete

[mjowen]

Is your feature request related to a problem? Please describe.
When tab completing to access properties of an ABM (model. followed by pressing tab), the fields of the ABM are shown (which can't be accessed by the model. syntax)

Describe the solution you'd like
Add a new method dispatch on propertynames for ABMs. Similar ones need doing for AgentWrapperSoA and for ReinforcementLearningABM. This should enable the autocompleting. Extending hasproperty too would save a bit of a headache based on whether the abmproperties are stored as a struct or a Dict