Fix bug: temp file for validate is not used and import from local delete original file

Dear Miles Johnson,
I have 2 problems when try import files from local with Model::save() from console.
1. I was debug and see problem about temp file in FileValidationBehavior class. It was delete original file after validate and make exception "No file detected in input stream".
2. I try use importFromLocal method same copy from remote, but it create many file for validate and only delete one temp file. 
This pull request is my simple solution for fix this problem.