Function annis_graphupdate_add_node 

#[unsafe(no_mangle)]
pub extern "C" fn annis_graphupdate_add_node(
    ptr: *mut GraphUpdate,
    node_name: *const c_char,
    node_type: *const c_char,
    err: *mut *mut ErrorList,
)

Add “add node” action to the graph update object.

• ptr - The graph update object.
• node_name - Name of the new node.
• node_type - Type of the new node, e.g. “node” or “corpus”.
• err - Pointer to a list of errors. If any error occurred, this list will be non-empty.