This template function writes a container of links to a stream.
LINKCNT should be a container as defined by the STL
*LINKCNT.valuetype must have a method
writeTo(ostream&), a method
Node *from() and a method
The data written to the stream will be of this form:
<size of the container> (<address of from() node> <address of to() node> [<additional info>] )*