mat-icon: Choose between Filled, Outlined, Rounded, Two-Tone and Sharp icons;

#### Please describe the feature you would like to request.
To be able to select between Filled, Outlined, Rounded, Two-Tone and Sharp when using mat-icon;

#### What is the use-case or motivation for this proposal?
An easy way to use the new icons available on https://material.io/tools/icons/?style=baseline (without having to manually put the SVG's of the icons you want)

Start by reviewing the mat-icon implementation and the Material Icons styles at the linked Material Design icons page. Determine how Filled, Outlined, Rounded, Two-Tone, and Sharp selections should be exposed through mat-icon, then verify that each style can be selected without manually supplying SVG files.

Written by the indexing model from the issue text.