[UI/UX] Sidebar Improvements, consistency fixes and Advanced Settings

[flavioislima]

This PR does mainly 3 things:

• Better Sidebar Consistency for colors and add a Settings Submenu
• Adds new Advanced Settings where we can put Debug options and more
• Fix Navigation confusing #919 by adding Back Buttons to game page and settings that work properly

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Use the following Checklist if you have changed something on the Backend or Frontend:

• Tested the feature and it's working on a current and clean install.
• Tested the main App features and they are still working on a current and clean install. (Login, Install, Play, Uninstall, Move games, etc.)
• Created / Updated Tests (If necessary)
• Created / Updated documentation (If necessary)

[Nocccer]

LGTM