Add some missing newlines

git_bbb/__init__.py

@@ -1,6 +1,7 @@
 """
 Git-bbb: Brisk Blame Browser for Git.
 """
+
 from prompt_toolkit import Application
 from prompt_toolkit.enums import EditingMode
 from prompt_toolkit.layout import Layout

git_bbb/git_plumbing.py

@@ -3,6 +3,7 @@
 Blame-related functionality is done by us instead of gitpython, becase the
 latter doesn't have all of the necessary functionality.
 """
+
 import os
 import re
 import subprocess