Use relative path as CMAKE input

Signed-off-by: Jean-Marie Verdun <jmverdun3@gmail.com>

.travis.yml

@@ -112,7 +112,7 @@ jobs:
             - $HOME/Library/Caches/Homebrew
             - /usr/local/Homebrew
         env:
-          - CMAKE_OPTS="-DCMAKE_CXX_COMPILER_LAUNCHER=/usr/local/bin/ccache -DBUILD_QT5=ON -DUSE_PYTHON3=1 -DCMAKE_CXX_FLAGS='-std=c++11' -DBUILD_FEM_NETGEN=1 -DBUILD_FEM=1 -DCMAKE_PREFIX_PATH='/usr/local/Cellar/qt/5.15.1/lib/cmake;/usr/local/Cellar/nglib/v6.2.2007/Contents/Resources' -DBUILD_FEM_NETGEN:BOOL=ON -DFREECAD_USE_EXTERNAL_KDL=ON -DCMAKE_BUILD_TYPE=Release"
+          - CMAKE_OPTS="-DCMAKE_CXX_COMPILER_LAUNCHER=/usr/local/bin/ccache -DBUILD_QT5=ON -DUSE_PYTHON3=1 -DCMAKE_CXX_FLAGS='-std=c++11' -DBUILD_FEM_NETGEN=1 -DBUILD_FEM=1 -DCMAKE_PREFIX_PATH='/usr/local/opt/qt/lib/cmake;/usr/local/opt/nglib/Contents/Resources' -DBUILD_FEM_NETGEN:BOOL=ON -DFREECAD_USE_EXTERNAL_KDL=ON -DCMAKE_BUILD_TYPE=Release"
           - PATH=/usr/local/bin:$PATH
           - CACHE_NAME=OSX1