Add execution bit for .travis.yml (refs #71)

Author: scheibel

.travis.yml

@@ -26,6 +26,7 @@ matrix:
 before_install:
   - if [ $TRAVIS_OS_NAME == linux ]; then sudo apt-get install -qq cmake qt5-default cppcheck clang-tidy-3.8; fi
   - if [ $TRAVIS_OS_NAME == osx ]; then brew update && brew install qt5 cppcheck; fi
+  - chmod +x ./configure
 
 before_script:
   - ./configure