Added testcases for comments

public_tests.txt

@@ -6,6 +6,7 @@ basic/check_error/invalid_for_loop_type.cvc
 basic/check_error/invalid_return_type.cvc
 basic/check_error/invalid_statements.cvc
 basic/check_error/undefined_var.cvc
+basic/check_error/unterminated_comment.cvc
 basic/check_success/binops.cvc
 basic/check_success/boolop.cvc
 basic/check_success/do_while.cvc
@@ -24,6 +25,8 @@ basic/check_success/parse_operators.cvc
 basic/check_success/parse_typecast.cvc
 basic/check_success/parse_vardec.cvc
 basic/check_success/vardec_init.cvc
+basic/check_success/comment_singleline.cvc
+basic/check_success/comment_multiline.cvc
 basic/combined_extern_var/defs.cvc
 basic/combined_extern_var/expected.out
 basic/combined_extern_var/main.cvc

test/basic/check_error/unterminated_comment.cvc

@@ -0,0 +1 @@
+/* you didn't have to cut me of ...

test/basic/check_success/comment_multiline.cvc

@@ -0,0 +1,5 @@
+/*
+ * multiple lines!
+ */
+int a;
+/* one line */

test/basic/check_success/comment_singleline.cvc

@@ -0,0 +1,2 @@
+// this should not yield a syntax error
+int a;

test/basic/check_success/comment_with_code.cvc

@@ -0,0 +1,4 @@
+void /**/ foo(int p/*
+          sometimes I believe the compiler ignores all my comments */) {
+    // nothing to see here
+}/**/