Updated roadmap

Here it comes, the updated roadmap.

Code base clean up

• Code style cleanup: I'm not satisfied with current astyle options so I would like to make the code pretty and separate methods with a line, and also separate different classes that lives in the same source file.
• Use RapidXML instead of TinyXML: RapidXML is fastest and has just one header file.
• Merge OIS with InputManager class.

Faster and better UI

• Use new Gorilla 2D drawing library for console and FPS (either by including it or forking the code if it fits better my needs), instead of Ogre's overlay. Gorilla can draw formatted text as well.
• Replace current Intro game state implementation using Gorilla instead of CEGUI.
• Fix console typing.
• Implement a simple GUI system with Gorilla in order to avoid CEGUI dependency.
• Replace current MainMenu game state implementation using Gorilla instead of CEGUI.

Advancement in scene rendering

• Correct sun and ambient dynamic lighting (including nice sunshine).
• Improve sun colour gradient and ambient light gradient colour.
• Avoid using terrain's lightmap when using a dynamic sky.
• Disable terrain's composite map until glitches are fixed.
• Fix terrain's composite map glitches.
• Implement camera and viewport setup from dotScene files.
• Use SkyX cloud layers until volumetric clouds work fine with OpenGL.
• Fix SkyX volumetric clouds glitches when rendering with OpenGL.
• Load procedural grass.
• Experiment with Deferred Shading instead of Forward Rendering.