Renamed README to README.md and added build status from Travis.
*LLVM-based* D compiler.
Rewrap to 70 characters.
Removed brief build instructions.
README: We no longer support D1.
Updated README with D wiki links.
Added first draft of useful README.
Needs to be expanded with a short section on contributing (and a
separate CONTRIBUTING file, for the GitHub feature), ...
LICENSE also needs an overhaul, and our files need license headers.