convert README to markdown #825

README

-Nix is a purely functional package manager.  For installation and
-usage instructions, please read the manual, which can be found in
-`docs/manual/manual.html', and additionally at the Nix website at
-<http://nixos.org/>.
-
-
-Acknowledgments
-
-This product includes software developed by the OpenSSL Project for
-use in the OpenSSL Toolkit (http://www.OpenSSL.org/).

README.md

+Nix, the purely functional package manager
+------------------------------------------
+
+Nix is a new take on package management that is fairly unique. Because of it's
+purity aspects, a lot of issues found in traditional package managers don't
+appear with Nix.
+
+To find out more about the tool, usage and installation instructions, please
+read the manual, which is available on the Nix website at
+<http://nixos.org/nix/manual>.
+
+## License
+
+Nix is released under the LGPL v2.1
+
+This product includes software developed by the OpenSSL Project for
+use in the OpenSSL Toolkit (http://www.OpenSSL.org/).