CADCraft guides

1. 01How to install CADCraft on macOS, Windows and LinuxWhich CADCraft 0.5.0 file to download for your OS and CPU, how to verify it, and how to build CADCraft from source. Based on the official README and the v0.5.0 release.
2. 02CADCraft: a free, open-source Autodesk AutoCAD alternativeWhat CADCraft 0.5.0 is, what it already does, and where it still falls short of Autodesk AutoCAD. Based only on the official CADCraft README and docs.