logstash-1.2.0 new event schema
 only @timestamp and @version are mandatory fields.
 everything else can go under @fields
 All custom fields are configured through fieldProperties
  a comma separated list of system property names.

Includes contributions from Christopher Kolstad <christopher.kolstad@gmail.com>
Signed-off-by: mck <mick@semb.wever.org>
Merge branch 'bugfix/fixes-for-logstash-1.2' into release/finn-no