Use correct ReST syntax and format

Signed-off-by: Philippe Ombredanne <pombredanne@nexb.com>

Author: pombredanne

CHANGES.txt

@@ -1,12 +1,12 @@
 ``pkginfo2`` Changelog
-=====================
+=======================
 
 30.0.0 (2022-01-28)
-------------------
+--------------------
 
 - Forked and rename to pkginfo2. Removed ability to import or eval packages
   or modules.
-
+- Move the bzr history to git
 
 1.8.2 (2021-12-01)
 ------------------

README.txt

@@ -1,5 +1,5 @@
 ``pkginfo2`` README
-==================
+=====================
 
 Homepage URL: https://github.com/nexB/pkginfo2
 SPDX-License-Identifier: MIT

setup.py

@@ -17,6 +17,7 @@
     description='Query metadatdata from sdists / bdists / installed packages. Safer fork of pkginfo to avoid doing arbitrary imports and eval()',
     platforms=['Unix', 'Windows'],
     long_description='\n\n'.join([README, CHANGES]),
+    long_description_content_type= 'text/x-rst',
     keywords='distribution sdist installed metadata',
     url='https://github.com/nexB/pkginfo2',
     author='Maintained by nexB, Inc. Authored by Tres Seaver, Agendaless Consulting',