Enhancements to p4d_base:
* Added $LOGS/p4d_init.log to track calls to init.
* Increased verbosity somewhat, though the 'p4d -xvu' output still
goes only to the p4d_init.log, with an error message referencing
that log in event of error.
* Replaced old preflight log with standard LOGFILE for all tracking.
* Fixed issue starting server due to LOGFILE not being defined;
not documented as a bug since it is a fix to unreleased behavior
in the last change in the dev branch.
* Enhanced to automatically replace '-d' with '--daemonsafe' if p4d
2017.1+
* Enhanced to call p4login rather than duplicating logic in p4login.
No rotation is provided for p4d_init.log; it is continuously appended
and is expected to grow only a few M per year with typical usage
(the bigger the server, the less the growth).
Enhancements to all *_base scripts:
* Enhanced so default behvaior, with no args, is to show a usage
message (rather than doing 'status').