Expose all fields (inc custom) as attributes (both get and set)
Custom fields :-
    load all custom fields using API on first API hit
    caches custom fields in local per entity json files (remove to update)
    converts the custom field keys to the field value
    When modifiying custom fields with set values, validates the new value
Links related objects automatically (person.org.deals)
    Creates stubs for them until the they get fully loaded then refreshes them
Handles modifying objects using attributes (including custom fields)
Keeps a list of modified fields
Added client.save_changes(entity)
Added automatic pagination
client.get_persons(limit=5000) will make up to 10 hits of 500 returning
all and refreshing any stubs
Retains access to raw json data (with .data)
Allows empty Client constructor if pipedrive_settings.json exists
Added examples folder

…rack fix attempts

…ble with the original branch - Now you need to import ooclient and set client with client = OOClient()