Consider consistent typography approach

**Enhancement**

When writing apps with consistent headings / subheadings etc it may be useful to provide a consistent approach.
This could be accomplished via css modules to be imported where required or by Widgets representing each typography type.

### css-modules

a css file like
```css
.heading1 {
font-size: 28px;
}
.heading2 {
font-size: 20px;
}
```
could be imported and used as such.

```tsx
import * as typography from '@dojo/widgets/typography';

return (
...
Title
Sub Title
...
);
```

### widgets

```tsx
import { Heading1, Heading2 } from '@dojo/widgets/typograhy';

return (
...
Title
Sub Title
...
);
```