Resolve "Missing status and mother_id in offline reader"

Closes #80 (closed)

km3io/offline.py

@@ -79,8 +79,8 @@ class OfflineReader(EventReader):
             "E": "mc_trks.E",
             "t": "mc_trks.t",
             "len": "mc_trks.len",
-            # "status": "mc_trks.status",  # TODO: check this
-            # "mother_id": "mc_trks.mother_id",  # TODO: check this
+            "status": "mc_trks.status",
+            "mother_id": "mc_trks.mother_id",
             "pdgid": "mc_trks.type",
             "hit_ids": "mc_trks.hit_ids",
             "usr": "mc_trks.usr",  # TODO: trouble with uproot4