The --force-handlers command line argument was not correctly running
handlers on hosts which had tasks that later failed. This corrects that,
and also allows you to specify force_handlers in ansible.cfg or in a
play.

- become constants inherit existing sudo/su ones
- become command line options, marked sudo/su as deprecated and moved sudo/su passwords to runas group
- changed method signatures as privlege escalation is collapsed to become
- added tests for su and become, diabled su for lack of support in local.py
- updated playbook,play and task objects to become
- added become to runner
- added whoami test for become/sudo/su
- added home override dir for plugins
- removed useless method from ask pass
- forced become pass to always be string also uses to_bytes
- fixed fakerunner for tests
- corrected reference in synchronize action plugin
- added pfexec (needs testing)
- removed unused sudo/su in runner init
- removed deprecated info
- updated pe tests to allow to run under sudo and not need root
- normalized become options into a funciton to avoid duplication and inconsistencies
- pushed suppored list to connection classs property
- updated all connection plugins to latest 'become' pe

- includes fixes from feedback (including typos)
- added draft docs
- stub of become_exe, leaving for future v2 fixes

refactored task selection into method
list-tasks now uses common method of task selection
always is now skippable if specified in --skip-tags

Adds new settings for managing retry files:
* retry_files_enabled, defaults to True
* retry_files_save_path, defaults to ~/.ansible-retry

This change was adapted from PR #5515.

  Only print a blank line between plays when also doing --list-hosts and/or
  --list-tasks, otherwise this output just a long list of blank lines, one for
  each play.

This allows `pip install -e` and `python setup.py develop` to work
without having to do the stuff in
http://docs.ansible.com/intro_installation.html#running-from-source so
it's a tad nicer for Python programmers who are accustomed to installing
packages as editable/in development mode.

Fixes GH-8355 (https://github.com/ansible/ansible/issues/8355)

Split out parsing of vars files to per host and per group
parsing, instead of reparsing all groups for each host. This enhances
performance.

Extend vars_plugins' API with two new methods:
* get host variables: only parses host_vars
* get group variables: only parses group_vars for specific group
The initial run method is still used for backward compatibility.

Parse all vars_plugins at inventory initialisation, instead of
per host when touched first by runner. Here we can also loop through
all groups once easily, then parse them.
This also centralizes all parsing in the inventory constructor.

	modified:   bin/ansible
	modified:   bin/ansible-playbook
	modified:   lib/ansible/inventory/__init__.py
	modified:   lib/ansible/inventory/vars_plugins/group_vars.py

Also add a unit test for vaulteditor to verify 1.0 passwords with newline chars.

Forward the vault_password to the yaml file utility.

This reverts commit c17d0e03.

Conflicts:
	lib/ansible/runner/connection_plugins/paramiko_ssh.py

This reverts commit 6f4bfa2c, reversing
changes made to c91ba3a7.

Fixes for ssh_alt support, adding in references to in_data where appropriate