README.md in bcupgrade-0.1.4 vs README.md in bcupgrade-0.2.0

@@ -87,9 +87,23 @@
 Atom.app (app)
 /Applications/Atom.app/Contents/Resources/app/apm/node_modules/.bin/apm (binary)
 /Applications/Atom.app/Contents/Resources/app/atom.sh (binary)
 ```
 
+
+## Configuration File
+
+in the user's `~/.bcupgrade` (YAML syntax).
+
+If you want to ignore upgrade casks, you can add settings.
+
+```
+ignore:
+  - omniplan1
+  - sublime-text2
+```
+
+
 ## Development
 
 After checking out the repo, run `bin/setup` to install dependencies.
 Then, run `rake spec` to run the tests.
 You can also run `bin/console` for an interactive prompt that will allow you to experiment.