Reorganize project into meaningful subfolders

[thekovic]

Is your feature request related to a problem? Please describe.
The Delphi project file is currently organized in a very flat way. The project files, the source files, the resource files, and the build output files all live in the src folder. The only exception is the DirectX 5 conversion in the d3d subfolder.

Describe the solution you'd like
Move the .dproj and .dpr project files into the repository root, move resource assets such as icons, cursors, and the generated .res files into a resource folder, set build output into a build folder (possibly also with different subfolders based on target platform and configuration). Additionally, the source files in the src folder could be placed into various meaningful subfolders (such as renderer, audio, forms, etc.).