Add tests for different suffix combos
Add tests for different suffix combos

This includes double suffixes (.pkl.gz), dots in file names
(name.1.1.jpg) and that the extensions get mapped from upper
to lower case.

yuxiang-zhou/menpo,grigorisg9gr/menpo,mozata/menpo,mozata/menpo,mozata/menpo,patricksnape/menpo,grigorisg9gr/menpo,yuxiang-zhou/menpo,menpo/menpo,menpo/menpo,grigorisg9gr/menpo,menpo/menpo,patricksnape/menpo,yuxiang-zhou/menpo,mozata/menpo,patricksnape/menpo