Support IPv6 in address check lookups.

This supports IPv6 in address DNS lookups and socket bind checks. Addresses are
looked up with the system getaddrinfo(), and the v6/v4 preference of this lookup
is respected. IPv6 address literals in the config file are expected to be
bracketed in [], and the result of lookups will be bracketed as well, to support
the ZeroMQ URI format.
Unset the IPV4ONLY socket option if available.

Since IPv6 sockets support both v4 and v6 addresses, the socket option is unset
unconditionally if the parameter is available in the zmq module. The actual
decision as to which address version to use is done by the address lookup code,
which obeys the system v4/v6 preference.
Be more resilient towards missing addresses and hostname lookup failures.
Add a unit test for passing IPv6-formatted addresses to verify_socket.
IPv6 address literals should be specified without brackets in config files.
Remove stray print.
Fix issues around `salt.modules.file`, `salt.states.files` and respective tests.

* Updated `salt.modules.file.makedirs` to properly work. Any path passed to this function should be a directory, ie, if `/tmp/foo/bar` is passed, `/tmp/foo/bar` should be a directory, not `/tmp/foo`.
* Since `salt.modules.file.makedirs` was updated, `salt.states.file.append` needed to be updated to pass the proper directory to create.
* Minor formatting change
Fix my wrong interpretation of `salt.modules.file.makedirs()`.
We want to create `path` not `dirname(path)`.
Handle `SaltReqTimeoutError` in a cleaner way.
Handle publish tests a little better. Still not fixed though.
Improve information available and handle `IndexError` in our salt asserts mix-in.
Fix `salt.states.file.directory()`. The logic was not accurate.
Merge pull request #4619 from UtahDave/develop

fix missing letter in module name
Merge pull request #4608 from s0undt3ch/develop

Fix issues with salt's file state and file module
Log rendered output at each stage
Moved render log data to better location
Fix indentation, again. Apparently I lost this change somehow.
Merge pull request #4624 from s0undt3ch/develop

Fix indentation, again. Apparently I lost this change somehow.
apt: replace aptitude with grep-available

This commit replaces the call to aptitude within list_pkgs with
grep-available, which dramatically speeds up virtual package detection.

This replaces the dependency on aptitude for virtual package detection
with a dependency on dctrl-tools.