LICENSE: update dragon4 license to MIT.

Ralf Gommers obtained written permission from Ryan Juckett on
15 June 2019 to distribute the dragon4-derived code under the
MIT license.

Note that the "one of a kind" designation in LICENSES_bundled.txt
wasn't quite correct: this was the Zlib license (which is less
well known, but also compatible with NumPy's BSD 3-clause license).

Closes numpygh-13674

LICENSES_bundled.txt

@@ -23,5 +23,5 @@ License: BSD derived
 
 Name: dragon4
 Files: numpy/core/src/multiarray/dragon4.c
-License: One of a kind
+License: MIT
   For license text, see numpy/core/src/multiarray/dragon4.c

numpy/core/src/multiarray/dragon4.c

@@ -1,31 +1,33 @@
 /*
  * Copyright (c) 2014 Ryan Juckett
- * http://www.ryanjuckett.com/
  *
- * This software is provided 'as-is', without any express or implied
- * warranty. In no event will the authors be held liable for any damages
- * arising from the use of this software.
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
  *
- * Permission is granted to anyone to use this software for any purpose,
- * including commercial applications, and to alter it and redistribute it
- * freely, subject to the following restrictions:
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
  *
- * 1. The origin of this software must not be misrepresented; you must not
- *    claim that you wrote the original software. If you use this software
- *    in a product, an acknowledgment in the product documentation would be
- *    appreciated but is not required.
- *
- * 2. Altered source versions must be plainly marked as such, and must not be
- *    misrepresented as being the original software.
- *
- * 3. This notice may not be removed or altered from any source
- *    distribution.
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
  */
 
 /*
  * This file contains a modified version of Ryan Juckett's Dragon4
- * implementation, which has been ported from C++ to C and which has
+ * implementation, obtained from http://www.ryanjuckett.com,
+ * which has been ported from C++ to C and which has
  * modifications specific to printing floats in numpy.
+ *
+ * Ryan Juckett's original code was under the Zlib license; he gave numpy
+ * permission to include it under the MIT license instead.
  */
 
 #include "dragon4.h"

numpy/core/src/multiarray/dragon4.h

@@ -1,31 +1,33 @@
 /*
  * Copyright (c) 2014 Ryan Juckett
- * http://www.ryanjuckett.com/
  *
- * This software is provided 'as-is', without any express or implied
- * warranty. In no event will the authors be held liable for any damages
- * arising from the use of this software.
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
  *
- * Permission is granted to anyone to use this software for any purpose,
- * including commercial applications, and to alter it and redistribute it
- * freely, subject to the following restrictions:
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
  *
- * 1. The origin of this software must not be misrepresented; you must not
- *    claim that you wrote the original software. If you use this software
- *    in a product, an acknowledgment in the product documentation would be
- *    appreciated but is not required.
- *
- * 2. Altered source versions must be plainly marked as such, and must not be
- *    misrepresented as being the original software.
- *
- * 3. This notice may not be removed or altered from any source
- *    distribution.
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
  */
 
 /*
  * This file contains a modified version of Ryan Juckett's Dragon4
- * implementation, which has been ported from C++ to C and which has
+ * implementation, obtained from http://www.ryanjuckett.com,
+ * which has been ported from C++ to C and which has
  * modifications specific to printing floats in numpy.
+ *
+ * Ryan Juckett's original code was under the Zlib license; he gave numpy
+ * permission to include it under the MIT license instead.
  */
 
 #ifndef _NPY_DRAGON4_H_