[FEATURE] - Support for Material Icons

[Lissy93]

Category: Feature

Overview
Adds support for icons from https://dev.materialdesignicons.com/icons
To use, first find the name of your icon, and then set: icon: mdi-[name-of-icon]

E.g.

sections:
- name: Material Design Icons
  items:
  - title: I'm an Alien
    icon: mdi-alien 
  - title: I'm warm
    icon: mdi-fire 
  - title: I'm a Dino
    icon: mdi-google-downasaur 

Issue Number #139

New Vars N/A

Screenshot

Code Quality Checklist (Please complete)

• All changes are backwards compatible
• All lint checks and tests are passing
• There are no (new) build warnings or errors
• (If a new config option is added) Attribute is outlined in the schema and documented
• (If a new dependency is added) Package is essential, and has been checked out for security or performance
• Bumps version, if new feature added

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[Lissy93]

👍 Will merge when all checks complete successfully.