(re)configure logging for SCION services

[juagargi]

Since the update in Dec. 2020, log messages from SCION services end up in the syslog of the system.
We also have the log level set to debug, which makes the system log overly populated.
Filter our SCION services' messages to a different file.

[cmeury]

In Progress

• Increase default log level from debug to info #349 will take care of changing the default log level we hand out in our configuration from debug to info.
• The hosts with heavy activity (attachment points) were configured with more aggressive log rotation as a short term remediation.

Still open

I'll verify that the log message are identical in the journal & syslog and if yes, will disable file logging altogether.