Update setup.cfg with description related fields

Add a package description and a content type for the long_description.

(DIS-1583)

setup.cfg

@@ -3,7 +3,9 @@ author = Dissect Team
 author_email = dissect@fox-it.com
 url = https://github.com/fox-it/dissect.etl
 license = Affero General Public License v3
+description = A Dissect module implementing a parser for Event Trace Log (ETL) files, used by the Windows operating system to log kernel events
 long_description = file: README.md
+long_description_content_type = text/markdown
 license_files = LICENSE, COPYRIGHT
 classifiers =
   Programming Language :: Python :: 3