Handle old host-regex properly as sub-domain in new ACL.

This resolves
     TODO clean up possible regex, if it starts with ".*"
     then store two entries: entry, and *dot*entry.
from an old comment.  I'd inadvertently implemented this direction of
mapping by mistake when I set out to do the - much easier (see
previous commit) - reverse transform and got confused.  So, might as
well not waste it.

Note that a regex that doesn't make sense as either a sub-domain match
or a simple domain name shall now be ignored, where it was previously
added to the host-name ACL; but, since it wouldn't have matched
anything anyway in the new-style ACL, there should be no harm in
omitting it.

(cherry picked from commit 08dce3a22d1e5c97adb5f664beb552d2b58886b0)
redmine4094: Infer start-time from elapsed when needed.

Some variants of ps report start-time as a date if before today (no
matter how recently today started) or even report a year for dates
before this year (even if new year's day started mere seconds ago).
These, naturally, give very imprecise information.  When that happens
but we have an elapsed time column (containing a value we can parse),
use this to infer a better start-time.  At the same time, improve
parsing of relevant time strings generally.  Based on a patch from
Tony Lill - many thanks.

Added an acceptance test.  Failed before the fix, passes with it :-)

(cherry picked from commit 881a1d51f996d2550d8de2151aee72a96ae8bf15)