* logging: revamped logs from content manager to be machine parseable
Logs from the content manager (except reads) are sent to separate log
file that is always free from personally-identifiable information
(e.g. no file names, just content IDs and blob IDs).
Also moved CLI logs to a subdirectory (cli-logs) and put content logs
in a parallel directory (content-logs)
Also, the log file name will now include the type of the command that
was invoked:
kopia-20200913-134157-16110-snapshot-create.log
Fixes#588
* tests: moved all logs from tests to a separate directory
f2cf71d914