preliminary privlege escalation unification + pbrun

- 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

lib/ansible/runner/action_plugins/unarchive.py

@@ -99,7 +99,7 @@ class ActionModule(object):
         # handle check mode client side
         # fix file permissions when the copy is done as a different user
         if copy:
-            if self.runner.sudo and self.runner.sudo_user != 'root' or self.runner.su and self.runner.su_user != 'root':
+            if self.runner.become and self.runner.become_user != 'root':
                 if not self.runner.noop_on_check(inject):
                     self.runner._remote_chmod(conn, 'a+r', tmp_src, tmp)
             # Build temporary module_args.