* Move GCP to a core extension
* Don't provide druid-core >.<
* Keep AWS and GCP modules separate
* Move AWSModule to its own module
* Add aws ec2 extension and more modules in more places
* Fix bad imports
* Fix test jackson module
* Include AWS and GCP core in server
* Add simple empty method comment
* Update version to 15
* One more 0.13.0-->0.15.0 change
* Fix multi-binding problem
* Grep for s3-extensions and update docs
* Update extensions.md