Postgres/StatusQuery: Fix concatenation and group by

refs #5896
ErrorController: Log exception and stacktrace

refe #5896
DowntimeQuery: Postgres fixes

Change is_fixed to boolean check and illegal postgres timerange of
'0000-00-00 00:00:00'.

refs #5896
NotificationHistoryQuery: Add missing field to group statement

refs #5896
Postgres/DbQuery: Add orderfields to select

refs #6896
CommandQuery: Remove select * from joins (Postgres)

refs #5896
GroupSummary/Postgres: Fix group by in initial join query

refs #5896
Merge branch 'bugfix/postgres-5896'

fixes #5896
fixes #6351
fixes #6350