[FEAT] Refactor Button Component

[xelaint]

💡 Feature request

Feature Name

Refactor Button Component

The Desired Behavior

Every button variant should be its own component, rather than it all being in one single component. They still share the same css class of .daff-button, with an extension of the variant name, i.e. .daff-flat-button

Your Use Case

As a developer, I would like to reduce the file size of the button component and unnecessary import of all button variants.

Prior Work

Environment

Daffodil version: X.Y.Z
Angular version: X.Y.Z 

 
For Tooling issues:
- Node version: XX  
- Platform:  

Others: