Image browser command bar : filtering and sorting improvement

Filtering

  1. Allow filtering by file extension on Windows
  2. More generally filtering using regular expressions on filenames and path names

Multi-criteria sorting, for example:

  1. date picture taken, descending
  2. file name, ascending
  3. file type: raw, dng, tif, jpg

Allow to consider as equivalent: jpg, jpeg, JPG and JPEG
Allow to consider as equivalent: tif, tiff, TIFand TIFF
Allow to consider as equivalent: dng, DNG