aren: rename files

Usage: aren {-d} [file1] [file2] {[file3] [file4]...}
Parameters:
-d: delete the destination file before rename (in order to avoid possible
  error messages - destination file names can only select non-existing names)

Examples:
aren -d test.txt final.txt
  -> rename test.txt to final.txt. If final.txt existed, it is first deleted

afind *.txt | aconv file "pathname + '.bak'" | axargs -i 2 aren -d FILE1 FILE2
  -> rename each .txt file to .bak