on linux try cmake 3.5.2

.travis.yml

@@ -41,7 +41,6 @@ matrix:
              # compilers
             - g++
             - gfortran
-            - cmake
               # math libraries
             - libblas-dev
             - liblapack-dev
@@ -66,10 +65,13 @@ install:
         pip install virtualenv
     elif [[ "${TRAVIS_OS_NAME}" == "linux" ]]; then
         pip install --user virtualenv
+        curl https://cmake.org/files/v3.5/cmake-3.5.2-Linux-x86_64.tar.gz | tar xvz
+        export PATH=~/cmake-3.5.2-Linux-x86_64/bin:$PATH
+        export LD_LIBARY_PATH=~/cmake-3.5.2-Linux-x86_64/lib:$LD_LIBRARY_PATH
     fi
   - virtualenv venv
   - source venv/bin/activate
-  - pip install pep8 pytest pyaml
+  - pip install -r requirements.txt
 
 script:
     # pep8 tests