improve logging

This allows for substantially more space for the log in an attempt to
actually capture more useful data.

Also ensure that whatever gets printed to stdout/stderr, such as C++'s
own exception handling, is considered very important and dropped by
accident.

Also relax the rate limit a bit; at least that ITMA polling on the
coherent A/D box produces a ton of data, and the trace bucket for that
service gets throttled.

A `journalctl -f -u systemd-journald` running in parallel was very
useful in debugging this.

Change-Id: If18446c9ab6c928a16e4944f331279cef627a612
Depends-on: https://cesnet-gerrit-czechlight/c/CzechLight/cla-sysrepo/+/1992
Depends-on: https://gerrit.cesnet.cz/c/CzechLight/cla-sysrepo/+/1992
diff --git a/package/cla-sysrepo/cla-appliance.service.in b/package/cla-sysrepo/cla-appliance.service.in
index 7ee5c31..c48bce3 100644
--- a/package/cla-sysrepo/cla-appliance.service.in
+++ b/package/cla-sysrepo/cla-appliance.service.in
@@ -18,6 +18,9 @@
 SystemCallArchitectures=native
 Restart=always
 WatchdogSec=15s
+LogRateLimitIntervalSec=10
+LogRateLimitBurst=30000
+SyslogLevel=alert
 
 [Install]
 WantedBy=multi-user.target