Minimize installed travis dependencies

Author: m-kuhn

.travis.yml

@@ -15,7 +15,7 @@ before_install:
   - sudo add-apt-repository ppa:ubuntugis/ppa -y
   - sudo add-apt-repository ppa:smspillaz/cmake-3.0.2 -y
   - sudo apt-get update -qq
-  - sudo apt-get install bison cmake cmake-data doxygen flex git graphviz grass-dev libexpat1-dev libfcgi-dev libgdal1-dev libgeos-dev libgsl0-dev libopenscenegraph-dev libosgearth-dev libpq-dev libproj-dev libqscintilla2-dev libqt4-dev libqt4-opengl-dev libqtwebkit-dev libqwt-dev libspatialindex-dev libspatialite-dev libsqlite3-dev lighttpd pkg-config poppler-utils pyqt4-dev-tools python python-dev python-qt4 python-qt4-dev python-sip python-sip-dev spawn-fcgi txt2tags xauth xfonts-100dpi xfonts-75dpi xfonts-base xfonts-scalable xvfb
+  - sudo apt-get install --no-install-recommends bison cmake cmake-data doxygen flex git graphviz grass-dev libexpat1-dev libfcgi-dev libgdal1-dev libgeos-dev libgsl0-dev libpq-dev libproj-dev libqscintilla2-dev libqt4-dev libqt4-opengl-dev libqtwebkit-dev libqwt-dev libspatialindex-dev libspatialite-dev libsqlite3-dev lighttpd pkg-config poppler-utils pyqt4-dev-tools python python-dev python-qt4 python-qt4-dev python-sip python-sip-dev spawn-fcgi txt2tags xauth xfonts-100dpi xfonts-75dpi xfonts-base xfonts-scalable xvfb
   - cmake --version
   - clang --version