public void unlink() {
            SortedBin neBin = parent.firstNonEmpty;
            if (neBin == this) {
                parent.firstNonEmpty = nextNonEmpty;
                return;
            }
            for (; ; ) {
                final SortedBin next = neBin.nextNonEmpty;
                if (next == this) {
                    neBin.nextNonEmpty = nextNonEmpty;
                    return;
                }
                neBin = next;
            }
        }
add a key value pair to the heap

@param key   the key to insert
@param value the value to insert object
main/src/main/java/cgeo/geocaching/brouter/util/SortedHeap.java