[Black] sync to develop branch and apply black

# Conflicts:
#	jrnl/EncryptedJournal.py
#	jrnl/Journal.py
#	jrnl/__init__.py
#	jrnl/cli.py
#	jrnl/install.py

.travis.yml

@@ -53,6 +53,13 @@ jobs:
     - os: windows
 
   include:
+    - stage: Lint & Tests
+      name: Lint, via Black
+      python: 3.8
+      # black is automatically installed by peotry
+      script:
+        - black --check . --verbose
+
     # Python 3.6 Tests
     - name: Python 3.6 on Linux
       python: 3.6