Fix namespace issues

Author: frederikfabriciusbjerre

NAMESPACE

@@ -13,18 +13,14 @@ export(E)
 export(V)
 export(add_edges)
 export(add_nodes)
-export(an)
 export(ancestors)
 export(as_caugi)
 export(as_igraph)
 export(build)
 export(caugi_graph)
-export(ch)
 export(children)
-export(de)
 export(descendants)
 export(edges)
-export(exo)
 export(exogenous)
 export(is_acyclic)
 export(is_caugi)
@@ -33,14 +29,9 @@ export(is_empty_caugi)
 export(is_pdag)
 export(length)
 export(markov_blanket)
-export(mb)
-export(nb)
-export(neighborhood)
 export(neighbors)
-export(neighbourhood)
 export(neighbours)
 export(nodes)
-export(pa)
 export(parents)
 export(print)
 export(register_caugi_edge)