Better licensing

This frees the Makefile and default.nix, adds SPDX headers, and
creates a LICENSES directory where files are named by SPDX identifier,
because with three licenses it starts getting excessive to have them
all in the root.

1 files changed, 2 insertions, 0 deletions

diff --git a/default.nix b/default.nix
index 6b05783..3f3b4aa 100644
--- a/default.nix
+++ b/default.nix
@@ -1,3 +1,5 @@
+# SPDX-License-Identifier: MIT
+
 with import <nixpkgs> {};
 
 stdenv.mkDerivation {