ttcn3-tcpdump-stop.sh: fix echo: add -e to enable colors

This change enables interpretation of backslash escapes for echo,
so the test case execution summary is always printed in color.

Change-Id: I0cc77b4de764c7afd6416512a181c4c1610ce369
diff --git a/ttcn3-tcpdump-stop.sh b/ttcn3-tcpdump-stop.sh
index 1f4da3d..30d331d 100755
--- a/ttcn3-tcpdump-stop.sh
+++ b/ttcn3-tcpdump-stop.sh
@@ -22,9 +22,9 @@
 date
 
 if [ x"$VERDICT" = x"pass" ]; then
-	echo "\033[1;32m====== $TESTCASE $VERDICT ======\033[0m"
+	echo -e "\033[1;32m====== $TESTCASE $VERDICT ======\033[0m"
 else
-	echo "\033[1;31m------ $TESTCASE $VERDICT ------\033[0m"
+	echo -e "\033[1;31m------ $TESTCASE $VERDICT ------\033[0m"
 fi
 echo