[Travis] Don't build with debug info

ci/travis/linux/before_install.sh

@@ -64,8 +64,3 @@ sudo -H pip install autopep8 # TODO when switching to trusty or above: replace p
 
 #update clang
 sudo apt-get install --force-yes llvm-3.7 llvm-3.7-dev clang-3.7 libstdc++-4.9-dev
-export CXX="clang++-3.7" 
-export CC="clang-3.7"
-
-cmake --version
-clang --version

ci/travis/linux/install.sh

@@ -1,9 +1,13 @@
 mkdir build
 cd build
+
 export CXX="clang++-3.7"
 export CC="clang-3.7"
-cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo \
-      -DWITH_SERVER=ON \
+
+cmake --version
+clang --version
+
+cmake -DWITH_SERVER=ON \
       -DWITH_STAGED_PLUGINS=OFF \
       -DWITH_GRASS=ON \
       -DSUPPRESS_QT_WARNINGS=ON \