Compound rules support

[raphschwander]

In the documentation, it is stated that compound rules also work

It recognises **[Bold Links](http://voyagetravelapps.com/)**
Or [**Bold Links**](http://voyagetravelapps.com/)

However, bold.font & bold.size are ignored in links

The issue can be reproduced in the example project.

Is this feature still supported ?

[nivbp7]

If the feature is still supported, could support be added for both bold and italic format of the same words?

For example:

let string = "**_multiple formatting_**"
let md = SwiftyMarkdown(string: string)

should be displayed as: multiple formatting