Fix a few typos in annotations/__init__.py

Found using mypy.

birdvisu/annotations/__init__.py

@@ -56,7 +56,7 @@ class AnnotatedTopology:
 		if ann_id in self.annotations:
 			if ann_id.annotator.idempotent: return None # Shortcut :-)
 			# Scrap old data before re-running
-			old_annot = self.annotatons[ann_id]
+			old_annot = self.annotations[ann_id]
 			for v in old_annot.for_vertex:
 				self.vertex_annotators[v].remove(ann_id)
 			for e in old_annot.for_edge:
@@ -67,7 +67,7 @@ class AnnotatedTopology:
 		annotator = ann_id.annotator(ann_id.param)
 		annotation = annotator.annotate(self)
 		for v in annotation.for_vertex:
-			self.vertex_annotation[v].add(ann_id)
+			self.vertex_annotators[v].add(ann_id)
 		for e in annotation.for_edge:
 			self.edge_annotators[e].add(ann_id)
 		if annotation.for_topology is not None: