Update README links and remove deprecated preferences modules (#51)

* update links

* remove deprecated preferences

* remove deprecated modules

Author: zskyfly

README.md

@@ -57,7 +57,7 @@ If you do not know how much to purchase, use an estimate.
 You can also create an order with a maximum desired price, and we'll allocate enough mass to
 fulfill the order for you.
 
-[API Reference](https://docs.usepatch.com/#/?id=orders)
+[API Reference](https://docs.patch.io/#/orders)
 
 #### Examples
 
@@ -105,7 +105,7 @@ patch.orders.retrieve_orders(page=page)
 
 Estimates allow API users to get a quote for the cost of compensating a certain amount of CO2. When creating an estimate, an order in the `draft` state will also be created, reserving the allocation of a project for 5 minutes. If you don't place your draft order within those 5 minutes, the order will automatically be cancelled.
 
-[API Reference](https://docs.usepatch.com/#/?id=estimates)
+[API Reference](https://docs.patch.io/#/estimates)
 
 #### Examples
 
@@ -162,7 +162,7 @@ When fetching projects, you can supply filters to the query to narrow your resul
 - `type`
 - `minimum_available_mass`
 
-[API Reference](https://docs.usepatch.com/#/?id=projects)
+[API Reference](https://docs.patch.io/#/projects)
 
 #### Examples
 
@@ -189,37 +189,6 @@ patch.projects.retrieve_projects(country="CA")
 patch.projects.retrieve_projects(minimum_available_mass=100)
 ```
 
-### Preferences
-
-Preferences are how you route your orders in Patch. If you don't have a preference, Patch will allocate your order to the least expensive option. If you do have a preference, all of your orders will be sent to that project. You can set your preferences via API, or through the [Patch Dashboard](https://dashboard.usepatch.com/projects).
-
-[API Reference](https://docs.usepatch.com/#/?id=preferences)
-
-#### Examples
-
-```python
-import patch_api
-
-patch = patch_api.ApiClient(api_key=os.environ.get('SANDBOX_API_KEY'))
-
-# Create a preference
-
-project_id = 'pro_test_1234' # Pass in the project_id for your preference
-patch.preferences.create_preference(project_id=project_id)
-
-# Retrieve a preference
-preference_id = 'pre_test_1234' # Pass in the preferences's id
-patch.preferences.retrieve_preference(preference_id=preference_id)
-
-# Delete a preference
-preference_id = 'pre_test_1234' # Pass in the preferences's id
-patch.preferences.delete_preference(preference_id=preference_id)
-
-# Retrieve a list of preferences
-page = 1 # Pass in which page of preferences you'd like
-patch.preferences.retrieve_preferences(page=page)
-```
-
 ## Contributing
 
 While we value open-source contributions to this SDK, the core of this library is generated programmatically. Complex additions made directly to the library would have to be moved over to our generation code, otherwise they would be overwritten upon the next generated release. Feel free to open a PR as a proof of concept, but know that we will not be able to merge it as-is. We suggest opening an issue first to discuss with us!