Reimplement resource storage and loading

[Kiriller12]

We need to reimplement resource storage and loading methods since it is not clear and simple enough to support new features at the moment.

[Kiriller12]

I think, this directory and file structure might be a good fit for this project.

Directory structure
	Data
		Shaders
			geometry.vert
			geometry.frag
			pointLighting.vert
			pointLighting.frag
			final.frag
			...
		Levels
			<name> folder or <name>.lvl zip archive
				metadata.json
		Models
			<name> folder or <name>.mdl zip archive
				metadata.json
				model.<3D model extension>
		Textures
			fallback.png
			texture.<image extension>
			...
		Animations
			animation.<animation extension>
			...
		Musics
			music.<sound extension>
			...
		Sounds
			sound.<sound extension>
			...
		Scripts
			script.lua
			script.luac
			...
		Videos
			video.<video extension>
		Localizations
			<name> folder or <name>.lng zip archive
				metadata.json
				font.<font extension>
				texture.<image extension>
				...
		<package name>.dgp zip archive
			Packed data archive. Can contain various data using directory structure mentioned above.
			For example:
				common.dgp
					Shaders
						geometry.vert
						geometry.frag
						pointLighting.vert
						pointLighting.frag
						final.frag
						...
					Textures
						fallback.png
						...
				game.dgp
					Levels
						...
					Models
						...
					Textures
						...
					Musics
						...
					Sounds
						...
					Scripts
						...
					Videos
						...
				localizations.dgp
					Localizations
						...
				mod1.dgp
					...
				mod2.dgp
					...