refactor(router): improve recognition and generation pipeline

This is a big change. @matsko also deserves much of the credit for the implementation.

Previously, `ComponentInstruction`s held all the state for async components.
Now, we introduce several subclasses for `Instruction` to describe each type of navigation.

BREAKING CHANGE:

Redirects now use the Link DSL syntax. Before:

```
@RouteConfig([
  { path: '/foo', redirectTo: '/bar' },
  { path: '/bar', component: BarCmp }
])
```

After:

```
@RouteConfig([
  { path: '/foo', redirectTo: ['Bar'] },
  { path: '/bar', component: BarCmp, name: 'Bar' }
])
```

BREAKING CHANGE:

This also introduces `useAsDefault` in the RouteConfig, which makes cases like lazy-loading
and encapsulating large routes with sub-routes easier.

Previously, you could use `redirectTo` like this to expand a URL like `/tab` to `/tab/posts`:

@RouteConfig([
  { path: '/tab', redirectTo: '/tab/users' }
  { path: '/tab', component: TabsCmp, name: 'Tab' }
])
AppCmp { ... }

Now the recommended way to handle this is case is to use `useAsDefault` like so:

```
@RouteConfig([
  { path: '/tab', component: TabsCmp, name: 'Tab' }
])
AppCmp { ... }

@RouteConfig([
  { path: '/posts', component: PostsCmp, useAsDefault: true, name: 'Posts' },
  { path: '/users', component: UsersCmp, name: 'Users' }
])
TabsCmp { ... }
```

In the above example, you can write just `['/Tab']` and the route `Users` is automatically selected as a child route.

Closes #4170
Closes #4490
Closes #4694
Closes #5200

Closes #5352

modules/angular1_router/test/integration/navigation_spec.js

@@ -113,8 +113,7 @@ describe('navigation', function () {
   });
 
 
-  // TODO: fix this
-  xit('should work with recursive nested outlets', function () {
+  it('should work with recursive nested outlets', function () {
     registerComponent('recurCmp', {
       template: '<div>recur { <div ng-outlet></div> }</div>',
       $routeConfig: [
@@ -152,8 +151,8 @@ describe('navigation', function () {
     compile('<div ng-outlet></div>');
 
     $router.config([
-      { path: '/',     redirectTo: '/user' },
-      { path: '/user', component:  'userCmp' }
+      { path: '/',     redirectTo: ['/User'] },
+      { path: '/user', component:  'userCmp', name: 'User' }
     ]);
 
     $router.navigateByUrl('/');
@@ -167,16 +166,15 @@ describe('navigation', function () {
     registerComponent('childRouter', {
       template: '<div>inner { <div ng-outlet></div> }</div>',
       $routeConfig: [
-        { path: '/old-child', redirectTo: '/new-child' },
-        { path: '/new-child', component: 'oneCmp'},
-        { path: '/old-child-two', redirectTo: '/new-child-two' },
-        { path: '/new-child-two', component: 'twoCmp'}
+        { path: '/new-child', component: 'oneCmp', name: 'NewChild'},
+        { path: '/new-child-two', component: 'twoCmp', name: 'NewChildTwo'}
       ]
     });
 
     $router.config([
-      { path: '/old-parent', redirectTo: '/new-parent' },
-      { path: '/new-parent/...', component:  'childRouter' }
+      { path: '/old-parent/old-child', redirectTo: ['/NewParent', 'NewChild'] },
+      { path: '/old-parent/old-child-two', redirectTo: ['/NewParent', 'NewChildTwo'] },
+      { path: '/new-parent/...', component:  'childRouter', name: 'NewParent' }
     ]);
 
     compile('<div ng-outlet></div>');