docs: Add copyright holders to license (#615)

* Add pyhf author names to setup.py
* Add the pyhf developers to the Apache license as the copyright holders

LICENSE

@@ -175,18 +175,7 @@
 
    END OF TERMS AND CONDITIONS
 
-   APPENDIX: How to apply the Apache License to your work.
-
-      To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "[]"
-      replaced with your own identifying information. (Don't include
-      the brackets!)  The text should be enclosed in the appropriate
-      comment syntax for the file format. We also recommend that a
-      file or class name and description of purpose be included on the
-      same "printed page" as the copyright notice for easier
-      identification within third-party archives.
-
-   Copyright [yyyy] [name of copyright owner]
+   Copyright 2018 pyhf Developers
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

setup.py

@@ -85,8 +85,8 @@ def _is_test_pypi():
     long_description=long_description,
     long_description_content_type='text/markdown',
     url='https://github.com/diana-hep/pyhf',
-    author='Lukas Heinrich',
-    author_email='lukas.heinrich@cern.ch',
+    author='Lukas Heinrich, Matthew Feickert, Giordon Stark',
+    author_email='lukas.heinrich@cern.ch, matthew.feickert@cern.ch, gstark@cern.ch',
     license='Apache',
     keywords='physics fitting numpy scipy tensorflow pytorch mxnet dask',
     classifiers=[