Rename source code directory to 'source'.
Remove .gitignore.

It was only useful for one directory, which I've moved out of the repository.
Rewrite parts of the Readme and consolidate the License into it.
Remove the 'docs' submodule.

The Wiki is very out of date and shouldn't be included with the
source code. If need be a person can clone it themselves.
Move models to the root directory and update call scripts.
Replace lighting.rbxl with an updated copy in the 'examples' directory.
Move guis.rbxl to the examples directory.