Small implementation improvements in MCF algorithms (#180)

- Handle max() as infinite value (not only infinity()).
- Better GEQ handling in CapacityScaling.
- Skip the unnecessary saturating operations in the first phase in
CapacityScaling.
- Use vector<char> instead of vector<bool> and vector<int> if it is
possible and it proved to be usually faster.

#!/bin/sh

# Run in valgrind, with leak checking enabled

valgrind -q --leak-check=full "$@" 2> .valgrind-log

# Save the test result

result="$?"

# Valgrind should generate no error messages

log_contents="`cat .valgrind-log`"

if [ "$log_contents" != "" ]; then

        cat .valgrind-log >&2

        result=1

fi

rm -f .valgrind-log

exit $result