Changing licence identifier

- Fixes #964

setup.cfg

@@ -4,7 +4,7 @@ version = 3.70.0
 url = https://github.com/jaedb/iris
 author = James Barnsley
 author_email = james@barnsley.nz
-license = Apache License, Version 2.0
+license = Apache-2.0
 license_file = LICENSE
 description = Fully-featured Mopidy frontend client
 long_description = file: README.rst
@@ -148,4 +148,4 @@ norecursedirs =
     .htaccess
     .vscode
     .vscode/*
-    .dockerignore
+    .dockerignore