Tweak and HISTORY.rst updates.

HISTORY.rst

@@ -3,11 +3,37 @@
 Release History
 ===============
 
+0.9.3
++++++++++++++++
+ * IoT Hub device identity import/export commands support usage via managed service identity using the --auth-type argument.
+ * Adds preview command group "az iot central app device"
+   * Adds preview command "az iot central app device create"
+   * Adds preview command "az iot central app device show"
+   * Adds preview command "az iot central app device list"
+   * Adds preview command "az iot central app device delete"
+   * Adds preview command "az iot central app device registration-info"
+	 * Adds preview command "az iot central app device registration-summary"
+ * Adds preview command group "az iot central app device-template"
+   * Adds preview command "az iot central app device-template create"
+   * Adds preview command "az iot central app device-template show"
+   * Adds preview command "az iot central app device-template list"
+   * Adds preview command "az iot central app device-template delete"
+   * Adds preview command "az iot central app device-template map"
+ * Changed how results are displayed in "az iot central app validate-messages"
+
+* Known issues:
+  * The following preview commands will retrieve at most 25 results
+	  * az iot central app device list
+	  * az iot central app device-template list
+    * az iot central app device-template map
+
+
 0.9.2
 +++++++++++++++
 * Device and module twin update operations provide explicit patch arguments (--desired, --tags).
 * Adds command "az iot central app validate-messages"
-* Remove Py 2.7 remnants from setup manifest.
+* Remove Py 2.7 support and remnants from setup manifest.
+* Remove Py 3.4 support and remnants from setup manifest.
 
 0.9.1
 +++++++++++++++

dev_requirements

@@ -10,4 +10,4 @@ flake8
 black;python_version>='3.6'
 wheel==0.30.0
 pre-commit
-six==1.12
+six>=1.12