Update for Fiend's Archive demo to version 0.2.7.

In this update, I changed multiple features of the game:

- UI rework.

- Textures rework: multiple item textures including the crossbow was changed.

- Changed the weapons reloading system.

- Added ragdoll physics for the AI.

- added particle effects to AI spawn, death, and going invisible.

- Mission log was updated to be easier to understand and follow.

- Changes in the environment lighting.

- Options menu rework.