Update LICENSE and NOTICE files

[jon-wei]

Updates the LICENSE and NOTICE files in preparation for the next release.

Notes:

• At one point we included a modified TestNG which was mentioned in our old NOTICE file. However, this was removed in Remove pached TestNG classes #5165, so I have removed references to that in LICENSE.
• We previously had a dependency on https://github.com/typetools/checker-framework introduced by Double-checked locking bugs #6662. The main project is GPL licensed, but the annotations it provides are MIT licensed. We only use annotations from this project, so this PR changes the dependency to checker-qual (just the annotations).
• Helper scripts for retrieving dependency info have been added to docs/_bin
• The LICENSE and NOTICE files are split into source-only and binary distribution versions, with associated packaging changes.
• Bundled licenses are stored in the licenses/src directory for source-level inclusions, and licenses/bin for binary-only dependencies
• The binary distribution now includes the README.md file along with the contents of a new LABELS.md file appended, used to hold licensing labels for Category B licenses (http://www.apache.org/legal/resolved.html#what-can-we-maybe-include-in-an-asf-project-category-b).

I am using the information at https://github.com/justinmclean/ApacheWombat as a reference for the process.

[jon-wei]

marking WIP, some of the "licenseFile" entries (pulled from node dependencies in web-console using a script) are not actually license files, will need to update those

will also need to add license for Bootstrap v3.1.1

[clintropolis]

I think the licenses/ folder needs to be excluded from rat check 🙃

[jon-wei]

We are still working with Apache Legal to resolve the Blueprint dependency questions, but this PR is ready for review otherwise.

[gianm]

It looks like one of the new files needs to be excluded:

[WARNING] Files with unapproved licenses:
  LABELS.md

Also, in light of #7139 the comment #7026 (comment) should be resolved, at least for now.

[jon-wei]

I've updated this to reflect the licenses after the Blueprint downgrade patch

[gianm]

The approach LGTM - after we get this confirmed as the right way to do things during our 0.14 release process, please go back and add documentation for future release managers. Thanks!!

[jon-wei]

@clintropolis @gianm Thanks for the review, I'll update this area with more documentation/automation for future release managers after 0.14.0.