Re-think integration vendoring

- remove docker/docker from  Traefik vendor (unused)
- use `ignore` for all Traefik vendor in integration glide.
- defined only integration specific version of the dependencies.

vendor/github.com/docker/docker/NOTICE

@@ -1,19 +0,0 @@
-Docker
-Copyright 2012-2016 Docker, Inc.
-
-This product includes software developed at Docker, Inc. (https://www.docker.com).
-
-This product contains software (https://github.com/kr/pty) developed
-by Keith Rarick, licensed under the MIT License.
-
-The following is courtesy of our legal counsel:
-
-
-Use and transfer of Docker may be subject to certain restrictions by the
-United States and other governments.
-It is your responsibility to ensure that your use and/or transfer does not
-violate applicable laws.
-
-For more information, please see https://www.bis.doc.gov
-
-See also https://www.apache.org/dev/crypto.html and/or seek legal counsel.