Add tests demonstrating incorrect empty relative path serialization b…

…y uri.path() and uri.pathname().

Clearly the relative path from"/a/b/c/" to "/a/b/c/" is the empty relative path "", and not "/".

Equivalently, URI("").path() should return the empty string "", but in fact returns "/".

The empty relative path is serialized correctly by .toString(), but incorrectly by .path() and .pathname().

test/test.js

@@ -155,6 +155,14 @@ test("path", function() {
     u.pathname('/~userhome/@mine;is %2F and/');
     equal(u.pathname(), '/~userhome/@mine;is%20%2F%20and/', "path encoding");
     equal(u.pathname(true), '/~userhome/@mine;is %2F and/', "path decoded");
+
+    u = new URI('/a/b/c/').relativeTo('/a/b/c/');
+    equal(u.pathname(), '', "empty relative path");
+    equal(u.toString(), '', "empty relative path to string");
+
+    u.pathname('/');
+    equal(u.pathname(), '/', "empty absolute path");
+    equal(u.toString(), '/', "empty absolute path to string");
 });
 test("query", function() { 
     var u = new URI("http://example.org/foo.html");