Removes forgotten sort() uses
Refactorized cleanDir() and improved getNormalizedExtension + normalizeExtension()
Removed deprecated use of $bad_directories property
Up to date phpdoc of cleanDir
Refactorized deleteDir()
Improvements of isDirEmpty(), huge optimization of renameDir() and small optimization to moveFiles()
Optimizes countFilesFromDir()
Renames hasExtension() method to hasExtensions() and make some optmizations on it
minor improvements to normalizeExtension() method
Huge optimization of rename() method
minor optimization to rename() method
minor improvements to compress() method
Fix possible issue with compress() method
minor improvements to getHigherSize() method
minor improvement to isImage() method
minor optimizations to resize() method
updates changelog