feat(COMPONENT): Schematic to generate all system variables used for each component

### Feature Description

Hi,

I'd like to suggest creation of a schematic to generate font typography config, exactly like the one for theme_colors:

` ng generate @angular/material:theme-color`

It would be used like this:

` ng generate @angular/material:theme-typography`

It would take 2 font names as options, and generate a full configuration with default values, making customization way more simple for us.

Right now, we all have a lot of old classes like mat-body, mat-display- ... etc, and the old typography definition is no longer really useable and we should probably get rid of it asap.

Problem is people are lost, and documentation is way too shallow to be used like it is.
A simple generation of configuration including all necessary tokens for typography would make things very simple, without having to search all over the place for bribes of documentation about this or that.

I hope you'll consider this.

### Use Case

This is to help every single Angular M2 project to transition smoothly to Angular M3

Beginne damit, das bestehende theme-color-Schema und die Anleitung zur Typografie-Konfiguration für Angular Material zu untersuchen. Lege fest, wie das neue Schema zwei Schriftartnamen akzeptieren soll, und ermittle die vollständige Menge der Typografie-Token und Standardwerte, die es generieren muss; als erledigt gilt die Aufgabe, wenn der Befehl eine verwendbare vollständige Konfiguration für die Migration auf Angular Material 3 erzeugt.

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