Rename org.topazproject packages to org.ambraproject

Any packages of the form org.topazproject.ambra.* had the "ambra" removed.
Update references to Topaz in comments
Delete org.ambraproject.Constants.ROOT_PACKAGE

Nothing was visibly using it, and it was set to the obsolete
"org.topazproject.ambra" package.
Merge remote-tracking branch 'origin/rename-topaz' into release/feb_r2