Add a cost scaling min cost flow algorithm.

Add a cost scaling algorithm, which is performing generalized
push-relabel operations. It is almost as efficient as the capacity
scaling algorithm, but slower than network simplex.

#!/bin/bash

cd ${0%update-libstd-tag}../doc

mv libstdc++.tag libstdc++.tag.old

wget http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/libstdc++.tag &&

rm libstdc++.tag.old || mv libstdc++.tag.old libstdc++.tag