Add rm utility and improve further

head.nim

@@ -2,6 +2,8 @@ import cligen, os, streams
 import common
 
 proc main(files:seq[string], lines=10, bytes=0) =
+#    if files.len == 0:
+#        files.add "-"
     for file in files:
         var s = newFileStream(file, fmRead)
         if bytes > 0: