add pytest-cov dependency

requirements.txt

@@ -13,6 +13,7 @@ numpy==1.13.3
 TA-Lib==0.4.10
 pytest==3.2.2
 pytest-mock==1.6.3
+pytest-cov==2.5.1
 
 # Required for plotting data
 #matplotlib==2.0.2

setup.py

@@ -13,7 +13,7 @@ setup(name='freqtrade',
       packages=['freqtrade'],
       scripts=['bin/freqtrade'],
       setup_requires=['pytest-runner'],
-      tests_require=['pytest', 'pytest-mock'],
+      tests_require=['pytest', 'pytest-mock', 'pytest-cov'],
       install_requires=[
           'python-bittrex==0.1.3',
           'SQLAlchemy==1.1.13',