2016-05-01: add test for multiline strings, currently failing with wisp.scm.

add test for multiline strings, currently failing with wisp.scm. Tracked down by Michael Lamb

diff --git a/tests/multiline-string.scm b/tests/multiline-string.scm
new file mode 100644
--- /dev/null
+++ b/tests/multiline-string.scm
@@ -0,0 +1,6 @@
+(display "
+  This is a
+  \"multi-line\"
+  string.
+  ")
+
diff --git a/tests/multiline-string.w b/tests/multiline-string.w
new file mode 100644
--- /dev/null
+++ b/tests/multiline-string.w
@@ -0,0 +1,5 @@
+display "
+  This is a
+  \"multi-line\"
+  string.
+  "