As per the new licensing change for Elasticsearch and Kibana this commit
moves existing Apache 2.0 licensed source code to the new dual license
SSPL+Elastic license 2.0. In addition, existing x-pack code now uses
the new version 2.0 of the Elastic license. Full changes include:
- Updating LICENSE and NOTICE files throughout the code base, as well
as those packaged in our published artifacts
- Update IDE integration to now use the new license header on newly
created source files
- Remove references to the "OSS" distribution from our documentation
- Update build time verification checks to no longer allow Apache 2.0
license header in Elasticsearch source code
- Replace all existing Apache 2.0 license headers for non-xpack code
with updated header (vendored code with Apache 2.0 headers obviously
remains the same).
- Replace all Elastic license 1.0 headers with new 2.0 header in xpack.
This commit moves the apache and elastic license files into a new
root level `licenses` directory and rewrites the top level LICENSE.txt
to clarify the repository has a mix of apache and elastic licensed code.