DO NOT MERGE Update README for rebrand

Author: dlangst

README.md

@@ -24,6 +24,13 @@ To install, use `pip`
 pip install --upgrade acd-sdk
 ```
 
+## Migrating from version 1.x.x
+
+The 2.0 release of the Annotator for Clinical Data SDK introduces a Python package name change from `ibm_whcs_sdk` to 'acd_sdk`.  For the migration from 1.x.x:
+
+1. After running `pip install --upgrade acd-sdk`, confirm that you have version 2.0 installed by running `pip show acd-sdk`.
+2. In your application files that have a dependency on `acd-sdk`, update any import declarations from `ibm_whcs_sdk` to `acd_sdk`.  
+
 ## Using the SDK
 For general SDK usage information, please see [this link](https://github.com/IBM/ibm-cloud-sdk-common/blob/master/README.md)