Design in-area map window

[SebastianJay]

Given the assets in #19, create a Window subclass which "renders" the 2D char array, using an indicator like different color to show which node the player is hovering over and showing a description of the place on the bottom of the screen. The player can use arrow keys to browse between different nodes, and can hit Enter/Return to exit the map view.

The window will be 35 (screen height) - 4 (help window and borders) = 31 rows and 120 (screen width) - 2 (borders) = 118 columns. Leave some space at the bottom (~3 rows) for a description of the selected room as well.