Merge pull request #1692 from freqtrade/feat/scripts_flake_mypy

run flake8 and mypy against scripts folder as well.

.travis.yml

@@ -39,9 +39,9 @@ jobs:
       - cp config.json.example config.json
       - python freqtrade --datadir freqtrade/tests/testdata hyperopt -e 5
       name: hyperopt
-    - script: flake8 freqtrade
+    - script: flake8 freqtrade scripts
       name: flake8
-    - script: mypy freqtrade
+    - script: mypy freqtrade scripts
       name: mypy
 
     - stage: docker