Removing final plugins and their installation as it is now handled via depedencies

This is the final step of plugin cleanup before 3.0 launch.

It works directly with the plugins change https://github.com/blackberry/cordova-blackberry-plugins/pull/69

As well as individual cordova plugin changes like the following https://github.com/apache/cordova-plugin-contacts/pull/2

cc @lorinbeer @bryanhiggins