Fix metadata of cwt.

setup.cfg

@@ -1,12 +1,12 @@
 [metadata]
 name = cwt
 version = attr: cwt.__version__
-author = attr: cwt.__author__
-author_email = attr: cwt.__email__
-description = attr: cwt.__description__
+author = AJITOMI Daisuke
+author_email = [email protected]
+description = A Python implementation of CWT (CBOR Web Token) and COSE (CBOR Object Signing and Encryption).
 long_description = file: README.md
 long_description_content_type = text/markdown
-license = attr: cwt.__license__
+license = MIT
 keywords = cbor cwt cose security signature encryption token
 url = https://github.com/dajiaji/python-cwt
 classifiers =