Merge pull request #7006 from jaredbeck/issue_7005_explain_asset_debug

A more informative comment for config.asset.debug

railties/lib/rails/generators/rails/app/templates/config/environments/development.rb.tt

@@ -35,7 +35,7 @@
   # Do not compress assets.
   config.assets.compress = false
 
-  # Expands the lines which load the assets.
+  # Debug mode disables concatenation and preprocessing of assets.
   config.assets.debug = true
   <%- end -%>