Fix bug # 1636437. Check UTI of dropped files before checking file content to determine if we can parse it. This allows parsing RIS files starting with comments as returned by Nature. 
Fix bug # 1636437. Check UTI of dropped files before checking file content to determine if we can parse it. This allows parsing RIS files starting with comments as returned by Nature. 

git-svn-id: cb3fc60f0f557b927b8032d8a94e869b6f9f230b@561 0fceea05-a30d-0410-8a8b-80ef821fb0a1

camillobruni/skim,jasongrout/skim,camillobruni/skim,camillobruni/skim,jasongrout/skim,camillobruni/skim