Output of CMake version, cleanup and formatting of CI config.

.travis.yml

           sources: *sources
 
 install:
-    - mkdir -p "${DEPENDENCY_DIR}" && cd "${DEPENDENCY_DIR}"
-    - |
-        if [[ ! -d "$(ls -A ${DEPENDENCY_DIR}/cmake)" ]]; then
-          CMAKE_URL="https://cmake.org/files/v3.8/cmake-3.8.2-Linux-x86_64.tar.gz"
-          mkdir -p cmake && travis_retry wget --no-check-certificate --quiet -O - "${CMAKE_URL}" | tar --strip-components=1 -xz -C cmake
-        fi
-        export PATH="${DEPENDENCY_DIR}/cmake/bin:${PATH}"
-    - cd ${TRAVIS_BUILD_DIR}
+  - mkdir -p "${DEPENDENCY_DIR}" && cd "${DEPENDENCY_DIR}"
+  - |
+      if [[ ! -d "$(ls -A ${DEPENDENCY_DIR}/cmake)" ]]; then
+        CMAKE_URL="https://cmake.org/files/v3.8/cmake-3.8.2-Linux-x86_64.tar.gz"
+        mkdir -p cmake && travis_retry wget --no-check-certificate --quiet -O - "${CMAKE_URL}" | tar --strip-components=1 -xz -C cmake
+      fi
+      export PATH="${DEPENDENCY_DIR}/cmake/bin:${PATH}"
+  - cd ${TRAVIS_BUILD_DIR}
 
 
 script:
-    - pwd
-    - ls
-    - script/ci_build.sh
+  - cmake --version
+  - script/ci_build.sh