Update .travis.yml

.travis.yml

@@ -15,6 +15,7 @@ addons:
       - g++
       - libgtest-dev
       - git
+      - cmake
       - openjdk-8-jdk
 install:
   - wget https://repo.continuum.io/miniconda/Miniconda3-latest-Linux-x86_64.sh -O miniconda.sh
@@ -28,7 +29,6 @@ install:
   - conda create -q -n test-environment python=$TRAVIS_PYTHON_VERSION
   - source activate test-environment
   - conda install numba
-  - conda install cmake
   - pip install coverage
   - pip install -U numpy
   - pip install scipy
@@ -43,7 +43,7 @@ install:
   - pip install finance-python --ignore-installed
   - pip install deprecated --ignore-installed
   - pip install cvxpy
-  - pip install xgboost
+  - pip install xgboost==0.90
   - export CWD=$PWD
   - cd /usr/src/gtest
   - sudo cmake CMakeLists.txt