improve title and description to make them intuitive

Author: KengoTODA

_apps/rtd-helper.md

@@ -1,8 +1,8 @@
 ---
 # A human-friendly name of your listing
-title: Read The Docs
+title: Read The Docs Helper
 # A short description of what your app does
-description: Assists reviewing using Read The Docs
+description: Assists reviewing using Read The Docs (RTD)
 # The slug of your hosted app on GitHub (https://github.com/apps/YOUR-SLUG)
 slug: rtd-helper
 # Include a few screenshots that show your app in action