We now need Boost headers to build with IMP on Python 3

tools/setup_ci.sh

@@ -9,8 +9,13 @@ fi
 
 python_version=$1
 
+if [ ${python_version} = "2.7" ]; then
+  BOOST=""
+else
+  BOOST="libboost-devel"
+fi
 conda config --remove channels defaults  # get conda-forge, not main, packages
-conda create --yes -q -n python${python_version} -c salilab -c conda-forge python=${python_version} pip imp-nightly gxx_linux-64 eigen cereal swig cmake numpy
+conda create --yes -q -n python${python_version} -c salilab -c conda-forge python=${python_version} pip imp-nightly ${BOOST} gxx_linux-64 eigen cereal swig cmake numpy
 eval "$(conda shell.bash hook)"
 conda activate python${python_version}
 pip install pytest-cov coverage