Organize Imports and Format Code

- standardizing all source
Alphabetize Observable.java

It’s a huge class … alphabetized the methods to give rhyme-and-reason for where to place new operators and for navigating it.
Revert to 1.8 for build to work ...

... until the build server handles 1.10.

Some odd issue with JUnit.
Back to 1.10 after building

... this still breaks the release build but I want to encourage us to get it working before we release again.
Update gradle.properties
0.16.2-SNAPSHOT
Make Observable Methods Final

Their behavior is interrelated and co-dependent and should therefore not be over-written.
Observable itself is not made final as there are some limited reasons for inheritance (such as GroupedObservable and Subjects).
Updating License Headers

- since I’m touching all files for the other commits I’ll update the copyright headers as well
Merge pull request #752 from benjchristensen/organize-format-alphabetize-finalize

Organize, Format, Alphabetize and Finalize