fix(input): input elements must use md-input attribute to be recognized

 - This is because a selector that finds the parent md-input-container is not supported fully by ng2.
 - update tabs demo to use md-input attributes.

BREAKING:

You must now put a md-input attribute on input elements inside of md-input-container in order to get material style support for them.

`<input md-input type="text">`

examples/components/tabs/dynamic_tabs.html

@@ -21,11 +21,11 @@ <h2 class="md-subhead">
     </div>
     <md-input-container>
       <label for="label">Label</label>
-      <input type="text" id="label" [(ngModel)]="tTitle">
+      <input md-input type="text" id="label" [(ngModel)]="tTitle">
     </md-input-container>
     <md-input-container>
       <label for="content">Content</label>
-      <input type="text" id="content" [(ngModel)]="tContent">
+      <input md-input type="text" id="content" [(ngModel)]="tContent">
     </md-input-container>
     <button md-raised-button class="add-tab md-primary" [disabled]="!tTitle || !tContent" type="submit">Add Tab
     </button>

ng2-material/components/input/input.ts

@@ -55,7 +55,8 @@ export class MdInputContainer implements AfterContentChecked {
 
 
 @Directive({
-  selector: 'md-input-container input',
+  selector: 'input[md-input],input.md-input',
+  providers: [MdInputContainer],
   host: {
     'class': 'md-input',
     '(input)': 'updateValue($event)',