Fix link to FPM
elasticsearch: send scrollid in post body

Newer elasticsearch versions have extremely long scrollids which pass
the URL limit.  Send the scrollid as part of the post body to avoid this
problem.
Merge pull request #935 from jdve/fix-elasticsearch-scrolling

elasticsearch: send scrollid in post body
Add coverage for tcp input event decoration w/ 'host' field
Only set 'host' field if it's not already set in the event.

Ditto for 'sslsubject'

This fixes a bug where tcp w/ json_lines codec would overwrite any
'host' setting with the client address on the other side of the
connection.
Merge pull request #937 from jordansissel/fix-tcp-input-event-decoration

Fix tcp input event decoration
Merge pull request #798 from simono/patch-1

Fix link to FPM