General update of several files with to do list

doc/src/Introduction/Introduction.do.txt

@@ -155,3 +155,18 @@ o Support vector machines and finally various variants of
 o Artifical neural networks and deep learning
 
 
+
+!split
+===== Why this text? =====
+
+
+!split
+===== Choice of programming language =====
+
+!split
+===== Data handling, machine learning  and ethical aspects =====
+
+
+!split
+===== Acknowledgements =====
+