OSS Licenses - output customization & visibility

**Describe the bug**

Some relation to #26 , addressing multiple issues/features

Output Customization:
1. It would be nice if there was some output customization. (related to #26 ) Where for example, Apache 2.0 license is sometimes linked. If there was a way to replace the link with text, that would be nice. So a way for users to point to a config file or something to overwrite.
1.a. Similarly, the copyright/attribution is missing in many cases. If there was a way to add the copyright statement (or missing information) to the results, that would be nice.
1.b. I am not sure the approach here, but I have noticed that Maven and GitHub sometimes show different licenses for projects. So if this plugin is looking to the maven repo, it may not be the correct license.

Visibility:
It appears that some of the results are deep/transitive dependencies. It would be nice to know where these dependencies are coming from. Is there a way to see that? I see some related files in app > build > generated > third_party_licenses

**Desktop (please complete the following information):**
- Gradle version: 5.1.1
- Android Studio version: 3.4.2
- Plugin name and version: com.google.android.gms:play-services-oss-licenses:16.0.2