Add get_selections() and set_selections() for dpkg.

This module will enable to freeze a package at a certain version, with the "hold" state.
Add TODO, amend later... FIXME.
Merge my dpkg-selections branch with develop.

Resolved conflicts in modules/apt.py.
Fix merge mistake.

urllib2 and json is part of standard Python.
Use yaml.safe_load()
Add another TODO
Use code-block

As per @terminalmage suggestion.
Add arg passing to wrapper funcs from top level
Add initial state wfunc module
fix bad ref to the minion's opts
silly pylint fix
Merge branch 'develop' into lxc
lxc: use gen_mac from salt.utils
Merge pull request #7010 from mgwilliams/docs

tweak docstrings
Merge branch 'develop' into lxc
Merge pull request #7012 from mgwilliams/lxc

lxc: use gen_mac from salt.utils
Bugfix for interacting with yum -- bug seen on CentOS 6.4, with Python 2.6 using pkg.installed.sources.
Only get the tags which match salt's version tags formatting.
Merge pull request #7015 from s0undt3ch/develop

Only get the tags which match salt's version tags formatting.
Merge pull request #7017 from pscripter/develop

Bugfix for interacting with yum -- bug seen on CentOS 6.4, with Python 2...