RavenGuard Build 0.4
v0.4 Goal:  Polish up and add QOL features to the inventory, and begin work on backend systems to control flow of level progression

Patch Notes:

UI
- Inventory / Unit Management screen updated
   - Correctly only displays the number of active alive units the player has, used to show 5 units even if some of them were dead
   - Can now swap items from units to the inventory and vis versa.
   - Highlights which units can use an item before selecting that item.
   - Pressing B or BACKSPACE is now context sensitive, no longer just exits out of the menu
   - Pressing X or E now unequips an item held by a unit and placed into the players inventory
   - Now displays description of the cover hovered skill

Levels and progression
(The below systems are currently in development, but have had progress reflected in the source code of this build)
- New system in development for creating levels by hand with art assets instead of generated at run time.
    - This will allow more detailed levels instead of procedurally generated art for levels that didn't always give good results.

Map
- Map node system to allow for player to choose which level to go to next

Art:
- Added app icon
- Various art assets for blacksmith building
     - Crate sprites
     - Anvil Sprites
     - Countertop Sprites
     - Barrel Sprites
     - Anvil Sprites
- Empty item slot UI Icon
- General UI Tileset
- Cavalry Class Portrait
- Cavalry Bow Attack Animation