Fix false positive in typedef rule for catch clause

src/rules/typedefRule.ts

@@ -185,7 +185,7 @@ class TypedefWalker extends Lint.RuleWalker {
         // catch statements will be the parent of the variable declaration
         // for-in/for-of loops will be the gradparent of the variable declaration
         if (node.parent != null && node.parent.parent != null
-                && node.parent.parent.kind !== ts.SyntaxKind.CatchClause
+                && (node as ts.Node).parent.kind !== ts.SyntaxKind.CatchClause
                 && node.parent.parent.kind !== ts.SyntaxKind.ForInStatement
                 && node.parent.parent.kind !== ts.SyntaxKind.ForOfStatement) {
             this.checkTypeAnnotation("variable-declaration", node.name.getEnd(), node.type, node.name);

test/rules/typedef/all/test.ts.lint

@@ -1,3 +1,8 @@
+// should not error with missing exception type
+try {
+} catch (e) {
+}
+
 var NoTypeObjectLiteralWithPropertyGetter = {
                                          ~    [expected variable-declaration: 'NoTypeObjectLiteralWithPropertyGetter' to have a typedef]
     Prop: "some property",