Restructured project documentation into two basically two
files at the top level.
README.md giving a rough project overview and information
and providing all information needed to build Swift, its
requirements and where to get them for all desktop platforms.
DEVELOPMENT.md is targeted at developers, describing the build
system, how to build only parts of the project. This document
also described how to build Swiften on Android and iOS, and
also covers testing and packaging guidelines.