fixes the now-incorrect module for ApiError

https://github.com/dotcloud/docker-py/blob/0.3.2/docker/errors.py
- ApiError is now(0.3.2) under the docker.errors
support old and new versions of APIError
apt_key clear message when downloading key returns an (http) error code
Backporting packaging updates from 1.6 branch
Merge pull request #7930 from trbs/apt_key_fetch_url_failure_codes

apt_key clear message when downloading key returns an (http) error code
Merge pull request #7925 from devpopol/fixes/api_error

fixes the now-incorrect module for ApiError -- noticed since 0.3.2
Success exit if sync=yes and no package provided
Successfull exit if sync=yes and no package provided
Merge pull request #7939 from PinGwynn/feature

portage: Successful exit if sync=yes and no package provided
Fixed FreeBSD ports install issue
Merge pull request #7942 from sidred10/devel

Fixed FreeBSD ports install issue