Update release notes and version name for 2.0.1.

Author: Elise Richards

app/build.gradle

@@ -21,8 +21,8 @@ android {
         minSdkVersion 24
         //noinspection OldTargetApi
         targetSdkVersion 26
-        versionCode 4824
-        versionName "2.0.0"
+        versionCode 4939
+        versionName "2.0.1"
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         // The following argument makes the Android Test Orchestrator run its
         // "pm clear" command after each test invocation. This command ensures

docs/release-notes.md

@@ -1,10 +1,18 @@
 # Release Notes
 
+## 2.0.1 (Build 4939)
+
+Cache access tokens.
+
+All changes since version 2.0.0:
+
+- Add token caching and token rotation (#945)
+
 ## 2.0.0 (Build 4824)
 
 Refine telemetry for sync and fix crashes.
 
-All changes since version 1.1.3: 
+All changes since version 1.1.3:
 
 - Telemetry for sync (#835)
 - String updates for localization (#852)