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
grammar fix
apt_key clear message when downloading key returns an (http) error code
In the yum module example, use present/absent instead of installed/removed
Fix missing code block in playbook variables doc

A code sample was not being rendered as a code block. This adds the preceding '::' reStructuredText markup.
Change safe_eval to a strict white list
Fix small typographic error
Merge pull request #7935 from mscherer/patch-1

Fix small typographic error
Merge pull request #7928 from timruffles/grammar

grammar fix
Merge pull request #7931 from quiver/fix-yum-module-doc

In yum module example, use present/absent instead of installed/removed
Merge pull request #7934 from chrishepner/patch-1

Fix missing code block in playbook variables doc
Additional fixes for safe_eval
Update RELEASES.txt
Update CHANGELOG.md
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