Rename "Realm" to "Atlas Device SDK" (#160)

Author: krollins-mdb

source/develop-applications.txt

@@ -26,7 +26,7 @@ Develop Applications
       :project-name: app-services
       :primary:
 
-   .. entry:: Realm SDKs
+   .. entry:: Atlas Device SDK
       :url: https://www.mongodb.com/docs/realm/
       :project-name: realm
       :primary: