Propagate setting dirty flags upwards

[AlexOxorn]

Fixes https://github.com/microsoftgraph/msgraph-sdk-ruby/issues/46

This PR is to fix 2 Issues

Issue 1

For the first issue, say I run the following code

    event = graph.me.events.find(outlook_id)
    event.start.date_time = DateTime.now.iso8601
    event.save!

it will not update the events start time.

By digging around, I noticed that if I call the date_time= method, though it sets the dirty flags for event.start but doesn't change event's dirty flags.

As a result, when it tries to serialize the event for updating, it will not serialize the start property.

Issue 2

For the second issue

say as a hack, to solve the first issue I run the following code

    event = graph.me.events.find(outlook_id)
    event.start.date_time = DateTime.now.iso8601
    event.start = event.start
    event.save!

this does set start as dirty, but the issue is the as_json method propagate the same options to its children. Since the only key in the options is based only on the @dirty_properties.keys of the event object, the options will look like { only: [:start] }

The issue with this is when it calls event.start.as_json(options) there are no options for start's dirty properties, causing the final json to look like { "start": { } } which causes an error.

Fix 1

To solve the first issue, when defining the properties, as part of the Base class, I add a instance_variable called @parent_property and @name which are passed in initialize_serialized_properties

klass.new(attributes: value, parent_property: self, name: property_key)

as well as add a function to deal with setting the dirty flags as well as propagate that upwards

    def set_dirty!(property_name)
      self.dirty = true
      self.dirty_properties[property_name] = true
      if parent_property.present?
        parent_property.set_dirty!(OData.convert_to_snake_case(self.name).to_sym)
      end
    end

Fix 2

To fix issue 2, I just make the as_json check if the value is a property object, then sets only to its dirty_properties

        result[k.to_s] = if MicrosoftGraph::Base === v
                           new_options = options.clone
                           new_options[:only] = v.dirty_properties.keys
                           v.as_json(new_options)
                         elsif v.respond_to?(:as_json)
                           v.as_json(options)
                         else
                           v
                         end

[msftclas]

All CLA requirements met.

[baywet]

Thank you for the contribution. We retired that version of the SDK a number of years ago and are now working on a new preview. You can learn all about it on the readme page.