Recursively search for directories that contain .dat files.

[ver228]

Currently the function compressMultipleFiles.py looks recursively for files with a given extension. However the .dat files of the new camera require rather a directory that contains .dat files inside. For the moment one can still use it by using as the search string the --pattern_include 'nameOfFirstImage.dat', but it will only work one file at the time (no multiple processes).

We should modify the function to specifically look for directories with dat files on it, and add a flag that activates this behaviour. More specifically we should modify or create an alternative to exploreDirs in compressMultipleFilesHelper.py

[ver228]

Linus changed it to tiff, and now one can look for the first file in the stack. The .hdf5 output will use the directory name as prefix.