add credstash lookup plugin

ansible-pull users rejoice

Restore ValueError in md5 method and change finding the available hash algorithms so we only have to do it once

Add get_available_hash_algorithms()

The "streamlined" syntax will be deprecated at some point in the future.

Fixes #11882

This is a slightly different fix than we originally committed, but fixes
the problem in a less invasive way (and I believe it's generally better
that we don't deal with relative paths internally past this point)

Fixes #11789

in view of simpler solution incomming from james
This reverts commit bae7a02b.

breaks handling constants.py errors gracefully

This reverts commit 59f96d71.

add documentation about any_errors_fatal

Path of group_vars and host_vars were getting the basedir added twice.

Add missed broadcast address to linux network facts.

Update README.md

Update README.md

Allow exceptions to pass through the program

This is useful when using `ipython --pdb -- $(which ansible-playbook)
...` for debugging.

Also show traceback when `ANSIBLE_DEBUG` is on

credstash lookup plugin: error out in run function when credstash not installed, not at module scope

Reformat commands to code format to make it stand out.

Fix missing download badge. Link to shields.io.

Fix inventory so this won't happen and fix DataLoader so that it will
test relative paths relative to self._basedir

Fixes #11789

Fixes #8261

* Better comments
* Reorganize code so related settings are close to each other
* Add ::1 to the "localhost" patterns we look for
* Make the dest_port parameter override the ansible_ssh_port setting
* Fix dest_port (wasn't being set)
* more complete detection of delegate_to
* Fix set_remote_user (wasn't being looked for in parameters)
* Instead of removing mode here, have the ansible module accept it
  (better documents the parameters doing it htat way)

So that roles are loaded ahead of all other play fields, meaning any
plugins contained within the roles are loaded first before tasks.

Fixes #11858