carrierwaveuploader/carrierwave — pull request #1321 by dimko (2014-02-17 11:38:45+00:00)
Title: Temp directory overflow issue

### Synopsis
Every `MiniMagick::Image.open(path)` call creates a temp file, which is not deleted after manipulating.
This leads to overflow of tmp directory under high load.

### Pull Request
1. Validate out image with `identify` command instead of opening an image.
2. Delete temp file after manipulate.