Match the description of the first parameter in the children confluence bridge w.r.t. N+1 children

[raphj]

confluence_children's first parameter behaves like documentTree's limit parameter:

In case there is only one child node remaining, the "more ..." link is replaced by that child node. This parameter is basically used to paginate the child nodes and thus helps the tree scale when the number of child nodes is large.

Make its description match this.