Adding Basic Menu System

[nicholas-maltbie]

Description

Added menu system with integration with networking state.

How Has This Been Tested?

Tested by running this locally on multiple clients as well as creating unit tests to verify the functionality of related components.

Checklist:

• [x] My code follows the style guidelines of this project
• [x] I have performed a self-review of my own code
• [x] I have commented my code, particularly in hard-to-understand areas
• [x] I have made corresponding changes to the documentation
• [x] My changes generate no new warnings

[github-actions[bot]]

Test Coverage Results for playmode: Line Coverage: 33.5% Link to run results: https://github.com/nicholas-maltbie/PropHunt-Mirror/actions/runs/506906135

[github-actions[bot]]

Test Coverage Results for playmode: Line Coverage: 33.5% Link to run results: https://github.com/nicholas-maltbie/PropHunt-Mirror/actions/runs/506912146

[github-actions[bot]]

Test Coverage Results for editmode: Line Coverage: 100% Link to run results: https://github.com/nicholas-maltbie/PropHunt-Mirror/actions/runs/506912146