* dirmngr/dirmngr.c (HOUSEKEEPING_INTERVAL): New.
(housekeeping_thread): New.
(handle_tick): Call new function.
* dirmngr/ks-engine-hkp.c (RESURRECT_INTERVAL): New.
(struct hostinfo_s): Add field died_at and set it along with the dead
flag.
(ks_hkp_print_hosttable): Print that info.
(ks_hkp_housekeeping): New.
--
The resurrection gives the host a chance to get back to life the next
time a new host is selected.
We better do this once and for all instead of cluttering all future
commits with diffs of trailing white spaces. In the majority of cases
blank or single lines are affected and thus this change won't disturb
a git blame too much. For future commits the pre-commit scripts
checks that this won't happen again.