Test data for RAW high dynamic range merging

* the data contains a set of .CR2 raw images taken with a Canon 5D mark II
* the exposures where done on a tripod in manual mode, the EXIF information is correct
* only the exposure times were varied:

IMG_7220.CR2
Exposure Time                   : 1
IMG_7221.CR2
Exposure Time                   : 1/5
IMG_7222.CR2
Exposure Time                   : 1/20
IMG_7223.CR2
Exposure Time                   : 1/80
IMG_7224.CR2
Exposure Time                   : 1/320
IMG_7225.CR2
Exposure Time                   : 1/1250

* Author: Ivo Ihrke, ~2011, Universität des Saarlandes / MPI Informatik