Add vendor exception for PhoneGap/Cordova device-specific JavaScript libraries.

Projects using the [PhoneGap](https://github.com/phonegap) framework for creating cross-platform mobile applications contain one or more copies of a `cordova.js` file, which serves as a bridge between the project's code (written in JavaScript) and the device. Each platform has a slightly different version of this large library, so a mobile application can contain 5 or more copies of the file, even though it's really a library (and not part of the application's code).

PhoneGap is widely used, and there are many projects on GitHub using it. For example, the [phonegap-start](https://github.com/phonegap/phonegap-start) project has over 3,000 forks.

This pull request treats files with names like "cordova.js", "cordova-1.2.0.js", "cordova.min.js", etc. as libraries and does not count them as part of a project's codebase.