Implement escape menu

[apachano]

When the user presses the escape key, an escape menu should pop up. Currently, there is no content for this menu, but in the future, it will house settings, as well as allow Lua to register menus.

• For this first implementation, the option to exit the game should be available as well as return to the game.
• The menu should be navigatable both with the mouse and the keyboard.
• This should be implemented in Quarts and be included when a window is created in Pheonix with no action taken in Pheonix.

Blocked by:
#169
#171