Remove relicensing file, update CONTRIBUTING for license changes.

CONTRIBUTING

@@ -48,6 +48,5 @@ requests on GitHub.
 
 Licensing
 ---------
-Dulwich is currently licensed under the GNU General Public License, version 2
-or later. We would like to change the license to Apachev2 or later eventually;
-new contributions should be made under dual GPLv2+/Apachev2+.
+All contributions should be made under the same license that Dulwich itself comes under:
+both Apache License, version 2.0 or later and GNU General Public License, version 2.0 or later.

relicensing-apachev2.txt

@@ -1,12 +0,0 @@
-At the moment, Dulwich is licensed under the GNU General Public License,
-version 2 or later.
-
-We'd like to relicense Dulwich under the Apache v2 (or later) license, as
-the GPL is problematic for many free software Python projects that are under
-BSD-style licenses. See also https://github.com/jelmer/dulwich/issues/153
-
-For reference, a full copy of the Apachev2 license can be found here:
-https://www.apache.org/licenses/LICENSE-2.0
-
-New contributions to Dulwich should be dual licensed under the GNU GPLv2 (or
-later) and the Apachev2 (or later) licenses.