Switch default log level to error

    - Change internal log level to error. As result a lot of messages
      are filtered out before they come to pmloglib.

Fixes:
    [GF-7427] Certain DB8 queries take over 2 minutes at 0% cpu/disk
    [GF-8333] Optimize use of DB8 to load records

Open-webOS-DCO-1.0-Signed-off-by: Maksym Sditanov <msditanov@luxoft.com>

Change-Id: Ifaacc97933d009022f1d55a178e598a68a437d8c
Reviewed-on: https://g2g.palm.com/2813
Reviewed-by: Build Verification
Reviewed-by: Maksym Sditanov <msditanov@luxoft.com>
Tested-by: Maksym Sditanov <msditanov@luxoft.com>
Reviewed-by: Nikolay Orliuk <norluk@luxoft.com>
Reviewed-by: Roger Stringer <roger.stringer@lge.com>