Add licenses for non-distributed third-party source code in repo

We have some software in the open-source JavaFX source-code repository that we don't distribute with the JDK. These fall into two categories:

1. Software that we use as part of demos, samples, or tests.

2. Software that we import as part of a larger thirs-party product, such as WebKit.

Even though this software is not distributed, we still need to list it in a clear manner, without requiring a developer to search through every file in the repository looking for such.