Add fluentd configuration for MySQL error.log

- changed default logging to log file
- parametrized log file path
- added fluentd configuration
- introduced fluentd multi_format parser plugin

Currently error logs sent to syslog are represented
with severity ERROR, which is misleading for Notice
and Warning messages during service startup/shutdown.

Change-Id: I55106775fa54b412b50ecc10c12930445da15d03
Related-bug: PROD-21904 (PROD:21904)
diff --git a/metadata/service/support.yml b/metadata/service/support.yml
index fb5051f..4fb4539 100644
--- a/metadata/service/support.yml
+++ b/metadata/service/support.yml
@@ -5,6 +5,8 @@
         enabled: true
       heka:
         enabled: true
+      fluentd:
+        enabled: true
       sensu:
         enabled: false
       sphinx: