feat(forms): Export NgSelectOption directive

Make the `NgSelectOption` directive visible from top-level forms module.

Author: Tim Blasi

modules/angular2/forms.ts

@@ -27,7 +27,10 @@ export {NgForm} from './src/forms/directives/ng_form';
 export {ControlValueAccessor} from './src/forms/directives/control_value_accessor';
 export {DefaultValueAccessor} from './src/forms/directives/default_value_accessor';
 export {CheckboxControlValueAccessor} from './src/forms/directives/checkbox_value_accessor';
-export {SelectControlValueAccessor} from './src/forms/directives/select_control_value_accessor';
+export {
+  NgSelectOption,
+  SelectControlValueAccessor
+} from './src/forms/directives/select_control_value_accessor';
 export {formDirectives} from './src/forms/directives';
 export {Validators} from './src/forms/validators';
 export {NgValidator, NgRequiredValidator} from './src/forms/directives/validators';
@@ -36,4 +39,4 @@ export {FormBuilder} from './src/forms/form_builder';
 import {FormBuilder} from './src/forms/form_builder';
 import {CONST_EXPR, Type} from './src/facade/lang';
 
-export const formInjectables: List<Type> = CONST_EXPR([FormBuilder]);
+export const formInjectables: List<Type> = CONST_EXPR([FormBuilder]);

modules/angular2/src/forms/directives.ts

@@ -23,7 +23,10 @@ export {NgForm} from './directives/ng_form';
 export {ControlValueAccessor} from './directives/control_value_accessor';
 export {DefaultValueAccessor} from './directives/default_value_accessor';
 export {CheckboxControlValueAccessor} from './directives/checkbox_value_accessor';
-export {SelectControlValueAccessor} from './directives/select_control_value_accessor';
+export {
+  SelectControlValueAccessor,
+  NgSelectOption
+} from './directives/select_control_value_accessor';
 export {NgValidator, NgRequiredValidator} from './directives/validators';
 
 /**
@@ -47,4 +50,4 @@ export const formDirectives: List<Type> = CONST_EXPR([
   SelectControlValueAccessor,
 
   NgRequiredValidator
-]);
+]);