Merge pull request plotly#271 from plotly/dash-image-processing

Dash image processing demo link fix

Author: YunkeXiao

apps/dash-image-processing/README.md

@@ -5,7 +5,7 @@ This is a demo of the Dash interactive Python framework developed by [Plotly](ht
 
 Dash abstracts away all of the technologies and protocols required to build an interactive web-based application and is a simple and effective way to bind a user interface around your Python code. To learn more check out our [documentation](https://plot.ly/dash).
 
-Try out the [demo app here](https://dash-playground.plotly.host/dash-iamge-processing/).
+Try out the [demo app here](https://dash-gallery.plotly.host/dash-image-processing/).
 
 ![screenshot](images/screenshot.png "Screenshot")