[bug] CORE-89 - Resolved issue with 0 byte files getting pulled into hotfolder...

... workflows

@dlamy 
@leafknode 

* 0 byte files were getting picked up by the poller when several files were dragged into a watchfolder
* sometimes permissions issues were causing file not found exceptions which were getting swallowed up, now printing filenotfound exceptions to the logs if warn is enabled.