Merge pull request TheAlgorithms#86 from frmatias/patch-2

Update .travis.yml

Author: harshildarji

.travis.yml

@@ -6,10 +6,9 @@ python:
   - "3.5"
   - "3.6"
   - "3.6-dev"
-  - "3.7-dev"
-  - "nightly"
+
 install: 
   - if [ "$TRAVIS_PYTHON_VERSION" == "3.2" ]; then travis_retry pip install coverage==3.7.1; fi
   - if [ "$TRAVIS_PYTHON_VERSION" != "3.2" ]; then travis_retry pip install coverage; fi
   - "pip install pytest pytest-cov"
-script: py.test --doctest-modules --cov ./
+script: py.test --doctest-modules --cov ./