partially revert last commit(DefaultStrategy import IS needed).

* don't run functions in travis in a way we don't support

.travis.yml

@@ -32,11 +32,11 @@ jobs:
       name: pytest
     - script:
       - cp config.json.example config.json
-      - python freqtrade --datadir freqtrade/tests/testdata backtesting
+      - freqtrade --datadir freqtrade/tests/testdata backtesting
       name: backtest
     - script:
       - cp config.json.example config.json
-      - python freqtrade --datadir freqtrade/tests/testdata hyperopt -e 5
+      - freqtrade --datadir freqtrade/tests/testdata hyperopt -e 5
       name: hyperopt
     - script: flake8 freqtrade scripts
       name: flake8

freqtrade/strategy/__init__.py

@@ -3,6 +3,8 @@ import sys
 from copy import deepcopy
 
 from freqtrade.strategy.interface import IStrategy
+# Import Default-Strategy to have hyperopt correctly resolve
+from freqtrade.strategy.default_strategy import DefaultStrategy  # noqa: F401
 
 
 logger = logging.getLogger(__name__)