Updates requested in PR diffblue#49: Added few code comments.

Author: marek-trtik

regression/december_demo_sprint/TRAINING/taint_traces_01/APP/taint_traces_01/Main.java

@@ -22,7 +22,7 @@ public static void branches(int x) {
         x = x - 2;
   }
 
-/*
+/*These methods are replaced be same methods are in Other class. Uncomment these, if you want to use them instead.
   public static void XX() {
     int xx = GG;
     GG = xx;
@@ -41,6 +41,8 @@ public static void test_stuff() {
     int a = 1;
     int b = 2;
 
+    /* next lines show how complex our instructions can be (they are not decomposed! :-( ) */
+
     int c = 5 * (8 * a + 9 * b) * n.next.next.next.value * 6;
 
     n.next.next.next.next.next.next = n.next.next.next.next.next.next.next.next;
@@ -65,7 +67,7 @@ public static int bar() {
     Main.bug(x1);
     return x1;
   }
-/*
+/*These methods are replaced be same methods are in Other class. Uncomment these, if you want to use them instead.
   public static int baz0(int a0) {
     return baz1(a0);
   }

regression/december_demo_sprint/TRAINING/taint_traces_05/APP/taint_traces_05/AssignmentAction.java

@@ -21,6 +21,10 @@ private HashMap uploadAll_parseZipFile(
         InputStream fileContentStream,
         HashMap submissionTable
         ) {
+    // If we do not load the class java.util.zip.ZipInputStream, then we
+    // loose the class hierarchy => our rules stop working correctly. The
+    // Introduced class XZipInputStream fixes the issue (i.e. important
+    // is that it inherits from java.io.InputStream).
     XZipInputStream zis = new XZipInputStream(fileContentStream);
     String comment = getBodyTextFromZipHtml(zis,true);
     submissionTable.put("some_key",comment);