Common logging setup for client and service

Common logging setup for client and service

[Issue#] N/A
[Feature/Bug] N/A
[Problem] Client may use different logging method than service.
[Cause] Service reads environment flags from config file. Client doesn't
[Solution] Make the client read that file too and setup log system properly.

[Verification] Make changes to /etc/sysconfig/central-key-manager file and see
if both service and client uses the same logging setup (provider and log level)
File format is the following:
"
CKM_LOG_PROVIDER=<provider>
CKM_LOG_LEVEL=<level>
"
where:
<provider> is one of JOURNALD, DLOG, CONSOLE
<level> is <0..5>, 0 means not logs at all, 1 means errors only, 5 means all

Change-Id: I1662fe636f9987778345f8a02afa6fb77f7f1fe0