Bugfix for logging lines without or delayed newlines

I found a solution for the issue
https://github.com/elasticsearch/logstash-forwarder/issues/149
Fixing some more issues (offset calculation, removing CR,...)

Fixed: file offset still calculated wrong. File was detected as
truncated again :-(
Fixed: loosing the beginning of a partial line
Fixed: A CR is also removed from the EOL

Known issues:
If the last line was logged with CRLF as EOF then the file offset is
not correct calculated (missing one byte for the CR) in the Registry
Small optimizations

Thanks to https://github.com/driskell
Only clean out prospector info of files we've stopped harvesting
Remove obsolete statement
Remove offset channel from harvester directly to registrar
Tidy and improve variable naming
Remove redundant comment
Merge branch 'tzahari/master' into driskell
Tidy registrar
Tweak startup events and always write registry