chore(docs) added a test for reference imports

test/test.js

@@ -87,6 +87,13 @@ describe('typescript-update', function() {
             var expected = "var x = 'some string';" + eol;
             assert.equal(tss.compile(src), expected);
         });
+
+        it('reference imports are ignored', function() {
+            var src = "/// <reference path='./typings/tsd'/> \
+            var x: number = 'some string';";
+            var expected = "var x = 'some string';" + eol;
+            assert.equal(tss.compile(src), expected);
+        });
 
         it('syntactic errors are not ignored', function() {
             var src = "var x = 123 123;";