Added printing of comments to *.actual test files

This enables testing of comment-handling code. Updated *.expected test
result files to account for printing of comments.

test/data/test_comment_02.expected

@@ -1,7 +1,14 @@
 .={}
+/* C-style comment
+
+    C-style-2 comment */
 .c-test={}
 .c-test.a=1
+/* Internal comment c-style */
 .c-test.b=2
+// C++-style comment
 .cpp-test={}
+// Multiline comment cpp-style
+// Second line
 .cpp-test.c=3
 .cpp-test.d=4