• Fix packit configuration: use upstream_tag_template: v{version}.
• Fix #33: Change the class ~deprecated.sphinx.SphinxAdapter: add
  the line_length keyword argument to the constructor to specify the
  max line length of the directive text. Sphinx decorators also accept
  the line_length argument.
• Fix #34: versionadded and versionchanged decorators don't emit
  DeprecationWarning anymore on decorated classes.