also remove condition to bypass setting user if user matches current user
this enables forcing user when set to the same user as current user and ignoring .ssh/config
while keeping .ssh/config with current user if nothing is specified.
* allow global no_log setting, no need to set at play or task level, but can be overriden by them
* allow turning off syslog only on task execution from target host (manage_syslog), overlaps with no_log functionality
* created log function for task modules to use, now we can remove all syslog references, will use systemd journal if present
* added debug flag to modules, so they can make it call new log function conditionally
* added debug logging in module's run_command
Due to the way we're now calculating delegate_to, if that value is based
on a loop variable ('item') we need to calculate all of the possible
delegated_to variables for that loop.
Fixes#12499
Also making PlayContext a child class of the Playbook Base class,
which gives it access to all of the FieldAttribute code to ensure
field values are correctly typed after post_validation
Fixes#11381
