Deleted unused class com.github.fritaly.dualcommander.DirectoryBrowser.FileListCellRenderer
Refactored code
Moved icons to a dedicated package "com.github.fritaly.dualcommander.icons.famfamfam"
In the table headers, use an icon to represent the current sort criteria & sort order
By default, always sort the file entries by ascending order
Don't display the last modified date for the parent directory
Updated class DirectoryBrowser to display a summary of the current directory (that is, the # of files & folders)