Add catches_strings test to test throws char * typemap

Examples/test-suite/javascript/catches_strings_runme.js

@@ -0,0 +1,15 @@
+var catches_strings = require("catches_strings");
+
+exception_thrown = false;
+try {
+  catches_strings.StringsThrower.charstring();
+} catch (e) {
+    console.log(typeof(e))
+    console.log(e.constructor.name)
+    console.log(typeof(e.message))
+  if (!e.message.includes("charstring message"))
+    throw new Error("incorrect exception message " + e.message);
+  exception_thrown = true;
+}
+if (!exception_thrown)
+  throw new Error("Should have thrown an exception");