Add link to AWS OSS Blog post

This fixes 745. Locked stacks still have dependencies, since there
is no difference between a locked stack and an unlocked stack at
creation time.

cloudtools#744)

* provider: add method to create, print, and delete a changeset for diff

* refactor diff command to use stack changeset rather than diff text

* provider: cleanup changeset temp stack, improve full output

* update providers/aws/test_default

- remove invalidated diff tests
- fixing aws provider tests
- add aws provider test for my changes
- linting fix

* blueprints: add method for retrieving output definitions

* add output handling for dependent stacks

* move most of logic to provider, fix issues with blueprints and rxref

* update tests for additions

* update docs

* update changelog

* sturdy -> onica

sturdy joined onica a good while ago ;)

* Update organizations_using_stacker.rst

* Add YAML environment file support

Environment files ending in .yaml or .yml will be rendered using
a different strategy. The env file is treated as a dict, with
the value for each key being a parsed YAML object. After parsing
the config, we look for things that look like variable references,
and replace the references with objects.

* Fix lint errors

* Fix more lint errors

Now with the correct version of flake8

* Fix IAM test errors due to missing version

Moto is requiring policy documents to be at least version
2012-10-17, so add that property.

* Fix python 2.7 issues

Python 2.7 strings and Python 3 strings work differently, and
regular expression matching is different too. Rewrite in a way
which works with both language versions.

* Remove debug printout

* Fix IAM test errors due to missing version (cloudtools#741)

Moto is requiring policy documents to be at least version
2012-10-17, so add that property.

* Use case insensitive file match

When checking for yaml suffixes on environment files, ignore
case.

* Add YAML environment file support

Environment files ending in .yaml or .yml will be rendered using
a different strategy. The env file is treated as a dict, with
the value for each key being a parsed YAML object. After parsing
the config, we look for things that look like variable references,
and replace the references with objects.

* Fix lint errors

* Fix more lint errors

Now with the correct version of flake8

* Fix python 2.7 issues

Python 2.7 strings and Python 3 strings work differently, and
regular expression matching is different too. Rewrite in a way
which works with both language versions.

* Remove debug printout

* Use case insensitive file match

When checking for yaml suffixes on environment files, ignore
case.

* Small documentation update

Yaml config example should use .yml file suffix, not .env

Co-authored-by: Marcin Romaszewicz <47459980+deepmap-marcinr@users.noreply.github.com>

* Fix ami lookup Name key error

* updating changelog

This fixes an issue with diffing based on changesets.  Before we
auto-diffed the parameters, even if it wouldn't result in a change in
the actual stack.  Now we require the stack to change before the diff
actually triggers.

This fixes the diff test for the raw template.

cloudtools#754)

* fix stack.set_outputs not being called if stack did not change

resolves cloudtools#753

* set_outputs for locked stacks

* add cf notification arns parameter

* fixed lint errors

* added NotificationARNs arg to test

* adjustments based on feedback, added test

	modified:   stacker/providers/aws/default.py
	modified:   stacker/stack.py
	modified:   stacker/tests/providers/aws/test_default.py

* docs

* pin more-itertools to version which supports py27
	modified:   setup.py

Co-authored-by: Tim Kukhmazov <Tim.kukhmazov@pnmac.com>

…specifiers (cloudtools#761)

see https://setuptools.readthedocs.io/en/latest/setuptools.html#declaring-dependencies

Co-authored-by: Tom Ritserveldt <tom.ritserveldt@gmail.com>

* Release 1.7.1

* pin "rsa" to a version which supports Python 2.7
	modified:   setup.py

* pin python-jose<3.2.0 because it dropped python 2.7

Co-authored-by: russellballestrini <russell.ballestrini@gmail.com>

Moto changed awslambda to be an extra, as of v1.3.15: https://github.com/spulec/moto/pull/3281/files

…udtools#765)

Co-authored-by: cfpipeline <cfpipeline@bt.com>