add the prefix feature to the src
refactor prefix feature - cast directly to service_buffer
handle prefix=null
Fix indentation, change Prefix to EventServicePrefix
Add documentation about the plugin in the pod file
ignore EventServicePrefix when its empty ("")
check the status of cf_util_get_string
rename prefix variable to eventServicePrefix
s/appended/used/ according to PR 706
Small naming conventions fixes, let the user to choose its delimiter
Merge remote-tracking branch 'github/pr/706'

Conflicts:
	src/write_riemann.c