Add unlicense

Author: pythoninthegrass

cookiecutter.json

@@ -18,6 +18,7 @@
   ],
   "create_author_file": "y",
   "open_source_license": [
+    "Unlicense",
     "MIT license",
     "BSD license",
     "ISC license",

{{cookiecutter.project_slug}}/LICENSE

@@ -1,4 +1,30 @@
-{% if cookiecutter.open_source_license == 'MIT license' -%}
+{% if cookiecutter.open_source_license == 'Unlicense' -%}
+
+This is free and unencumbered software released into the public domain.
+
+Anyone is free to copy, modify, publish, use, compile, sell, or
+distribute this software, either in source code form or as a compiled
+binary, for any purpose, commercial or non-commercial, and by any
+means.
+
+In jurisdictions that recognize copyright laws, the author or authors
+of this software dedicate any and all copyright interest in the
+software to the public domain. We make this dedication for the benefit
+of the public at large and to the detriment of our heirs and
+successors. We intend this dedication to be an overt act of
+relinquishment in perpetuity of all present and future rights to this
+software under copyright law.
+
+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 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.
+
+For more information, please refer to <https://unlicense.org>
+{% elif cookiecutter.open_source_license == 'MIT license' -%}
 MIT License
 
 Copyright (c) {% now 'local', '%Y' %}, {{ cookiecutter.full_name }}