Add script to automatically update AUTHORS file

TODO

@@ -1,8 +1,6 @@
 Before new_layout branch merge
 ==============================
 * README.md update (pull-request #145)
-* Script to automatically update file contents:
-    contributors    : AUTHORS
 
 
 After new_layout merge

devscripts/update-authors.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+
+# Author: Sotiris Papadopoulos <ytubedlg@gmail.com>
+# Last-Revision: 2017-04-17
+# Script to update the AUTHORS file
+#
+# Usage: ./update-authors.sh
+
+cd ..
+
+git log --reverse --format="%aN <%aE>" | python -c "
+
+import sys
+
+authors = set()
+
+sys.stdout.write('# Authors ordered by first contribution.\n\n')
+
+for line in sys.stdin:
+    username, _ = line.split('<')
+
+    if username not in authors:
+        authors.add(username)
+        sys.stdout.write(line)
+
+sys.stdout.write('\n# Generated by update-authors.sh script\n')
+" > AUTHORS