When you realize, you are creating plugin to call one function on the android side it's ...
Go to your cordova project and just copy paste the plugin there. Then run (in your project folder):
cordova plugin add ./cordova-example-plugin
You can have the plugin wherever you want, it doesn't have to be in you project path, but remember that may come time when someone else will be pulling your project from repository and he will have your plugin as a dependency.
Then in javascript:
cordova.exec(function(success) {}, //success callback
function(error) {}, //error callback
"Example", //class name
"YOUR_ACTION_NAME_PARAMETER", //action name
["Dog", "Pig", 42, false]); //args array