added completion for exports in named imports section

src/compiler/checker.ts

@@ -56,6 +56,7 @@ module ts {
             isImplementationOfOverload,
             getAliasedSymbol: resolveImport,
             getEmitResolver,
+            getExportsOfExternalModule,
         };
 
         var undefinedSymbol = createSymbol(SymbolFlags.Property | SymbolFlags.Transient, "undefined");
@@ -2754,6 +2755,19 @@ module ts {
             return result;
         }
 
+        function getExportsOfExternalModule(node: ImportDeclaration): Symbol[]{
+            if (!node.moduleSpecifier) {
+                return emptyArray;
+            }
+
+            var module = resolveExternalModuleName(node, node.moduleSpecifier);
+            if (!module || !module.exports) {
+                return emptyArray;
+            }
+
+            return mapToArray(module.exports)
+        }
+
         function getSignatureFromDeclaration(declaration: SignatureDeclaration): Signature {
             var links = getNodeLinks(declaration);
             if (!links.resolvedSignature) {

src/compiler/types.ts

@@ -1100,6 +1100,7 @@ module ts {
         getConstantValue(node: EnumMember | PropertyAccessExpression | ElementAccessExpression): number;
         isValidPropertyAccess(node: PropertyAccessExpression | QualifiedName, propertyName: string): boolean;
         getAliasedSymbol(symbol: Symbol): Symbol;
+        getExportsOfExternalModule(node: ImportDeclaration): Symbol[];
 
         // Should not be called directly.  Should only be accessed through the Program instance.
         /* @internal */ getDiagnostics(sourceFile?: SourceFile): Diagnostic[];