added AnchoredDumper
added to jinja load* filters and tags
added doc for yaml / json tags
try to fix travis exception
removed anchored yaml, does not work with CDumper...
finished cleanup
make it works for python 2.6
Fix some formatting in the mine
Merge pull request #6239 from basepi/minefix5729

Fix some formatting in the mine
Catch jinja2.exceptions.UndefinedError

This commit suppresses a traceback that occurs when there is an
undefined jinja variable used in a template. Unfortunately, it does not
seem that this exception class captures the name of the undefined
variable, which would be useful information, so a mention of the line
number in which the exception was found will have to be sufficient.
Clarify templating documentation for file states
Merge pull request #6241 from terminalmage/issue6020

Catch jinja2.exceptions.UndefinedError
Stop using the deprecated `check_dns` in `salt.config.minion_config`.
Properly deprecate `check_dns`.

Instead of having to leave `**kwargs` "forever" in `salt.config.minion_config` and `salt.config.apply_minion_config` in order to support API access to those which still passes `check_dns`. Support the argument but show a deprecation warning once. Leave the deprecation warning for 2 major releases. Then, finally, and properly, remove `check_dns` for good.
Added a helper function to raise warnings until a specified salt version.

The helper raises a warning, by default, a ``DeprecationWarning``, until the provided ``version_info`` is matched, after which, a ``RuntimeError`` will be raised to remember the developers to remove the warning.
**ALL** Salt `DeprecationWarning`'s should be shown **once**.
Replaced occurrences of `warnings.warn` with `salt.utils.warn_until`.
Allow `salt.utils.warn_until()` to not issue the warning because we're only after the `RuntimeError` behaviour.
Marked specific places which need code removal on salt >= 0.18
Document the deprecation procedure to follow and how to use the helper class.