installing cmake earlier in travis script

Author: markusgft

.travis.yml

@@ -25,6 +25,7 @@ before_install:
 
    #install gtest
   - sudo apt-get update                     >/dev/null # suppress output
+  - sudo apt-get install cmake              >/dev/null # suppress output
   - sudo apt install libgtest-dev           >/dev/null # suppress output
   - cd /usr/src/gtest/                      >/dev/null # suppress output
   - sudo mkdir build && cd build            >/dev/null # suppress output