[#75785372] Add one integration test for Client#get_properties

- Use new Savon 2 synxtax in client
[#75785372] Add integration test for Client#get_units
[#75785372] Add SoapClient class

To deal with soap-specific stuff
[#75785372] Move Property and PropertyParameters models to their own files
[#75785372] Refactor Client#get_properties to smaller classes

- Move away from stubbed savon services
- Have 1 integration test that records the actual request/response
[#75785372] Move code into a base class

Common request class behavior
[#75785372] Use original length for client_name validation
[#75785372] Refactor Client#get_property
[#75785372] Convert PropertyParameters from Modelish to Virtus
[#75785372] Refactor Client#get_property_parameters
[#75785372] Remove unmaintained comments and unnessary include
[#75785372] Extract models and use Virtus instead of Modelish
[#75785372] Refactor LeaseTermRentMethods
[#75785372] Refactor Client#get_floor_plan_amenities
[#75785372] Refactor Client#get_unit_amenities
[#75785372] Refactor Client#get_rent_summary
[#75785372] Refactor Client#get_available_units
[#75785372] Refactor Client#get_units
[#75785372] Refactor Client#get_unit
[#75785372] Do not send arguments to YieldStar with nil values