<mat-tab> Hide and Show Feature

#### Bug, feature request, or proposal:
hide/show behavior need to Provide in future release.

#### What is the expected behavior?

wanted to hide/show tab.
#### What is the current behavior?
currently you ppl are providing disabled feature so i wanted to hide/show tab.

#### What are the steps to reproduce?
provide api include hide/show feature.
#### What is the use-case or motivation for changing an existing behavior?
i need to show/hide tabs for that i need this feature instead of disabled api.

#### Which versions of Angular, Material, OS, TypeScript, browsers are affected?
i have used angular5 and Material design 5.2. please go through the below link for your reference.
https://material.angular.io/components/tabs/api

#### Is there anything else we should know?
apart from disable tab everything is working fine.

Inizia con l’Angular Material tabs API collegata nell’issue ed esamina il comportamento esistente delle schede disabilitate. Determina la semantica prevista di nascondimento/visualizzazione e l’implementazione e i test delle schede interessati; il lavoro è completo quando l’API e il comportamento sono chiaramente specificati e coperti da test.

Scritto dal modello di indicizzazione a partire dal testo della issue.