update docs to include a local pattern, adjust SDK token language (#369)

* update docs to include a local pattern, adjust SDK token language

Author: tim-quix

docs/quix-platform.md

@@ -26,20 +26,32 @@ Here is how to connect to the Quix Cloud Kafka brokers using Quix Streams:
 
 If you are running your Quix Streams `Application` directly within Quix Cloud, it's configured automatically.
 
+Just make sure `broker_address` is NOT set:
+
+```python
+from quixstreams import Application
+
+app = Application()
+```
+OR
+```python
+from quixstreams import Application
+
+app = Application(broker_address=None)
+```
+
 ### Outside of Quix Cloud
 
 
-#### 1. Obtain Streaming Token
-First, [get your Streaming
-Token](https://quix.io/docs/develop/authentication/streaming-token.html#how-to-find) (also
-called `SDK Token`).
+#### 1. Obtain SDK Token
+First, [get your SDK Token](https://quix.io/docs/develop/authentication/streaming-token.html#how-to-find).
 
 > NOTE: A `Personal Access Token` (PAT) is also accepted, but often requires more configuration 
 > due to raised privileges. We recommend using the `SDK Token`.
 
 <br>
 
-#### 2. Pass Streaming Token to Application
+#### 2. Pass SDK Token to Application
 With your `SDK Token` and a Quix Streams `Application`, you can pass it using one of
 these approaches:
 
@@ -50,7 +62,12 @@ these approaches:
 OR <br>
 
 - **Application argument** 
-    - Just do `Application(quix_sdk_token="MY_TOKEN")` 
+    - Just do:
+      ```python
+      from quixstreams import Application
+      
+      app = Application(quix_sdk_token="MY_TOKEN")
+      ```
   > WARNING: This value is prioritized over `Quix__Sdk__Token`, which may cause ambiguity if both are set.
 
 <br>
@@ -59,4 +76,20 @@ OR <br>
 When you initialize your `Application()`, a message should be logged letting 
 you know it will connect to Quix Cloud when `Application.run()` is called. 
 
-If not, you'll need to double check your settings and try again!
+If not, you'll need to double check your settings and try again!
+
+## Local Development to Quix Cloud
+
+For those wanting to [develop with a local broker](tutorials/README.md#running-kafka-locally) 
+and then migrate to Quix Cloud, here is a recommended example pattern that avoids code changes:
+
+```python
+from quixstreams import Application
+import os
+
+app = Application(broker_address=os.getenv("YOUR_ENV_VAR", None))
+```
+
+Just pick an environment variable and set it to your local broker address!
+
+In Quix Cloud it will default to `None` as desired and use the Quix Cloud environment.