Fix rocket.ParseError exception handling

Before, a tuple was crammed into args[0].  Now, the three arguments are
args[0:2].

nilmdb/server/bulkdata.py

@@ -367,7 +367,7 @@ class Table(object):
                      ) = f.append_string(count, data, data_offset, linenum,
                                          start, end, last_timestamp)
                 except rocket.ParseError as e:
-                    (linenum, errtype, obj) = e.message
+                    (linenum, errtype, obj) = e.args
                     if errtype == rocket.ERR_NON_MONOTONIC:
                         err = sprintf("line %d: timestamp is not monotonically "
                                       "increasing", linenum)
@@ -381,7 +381,7 @@ class Table(object):
                                           "end time %s", linenum,
                                           ftts(obj), ftts(end))
                     else:
-                        err = str(e)
+                        err = str(obj)
                     raise ValueError("error parsing input data: " + err)
                 tot_rows += added_rows
         except Exception:

nilmdb/server/pyrocket.py

@@ -112,12 +112,12 @@ class Rocket(object):
             try:
                 (ts, row) = self.layoutparser.parse(line)
             except ValueError as e:
-                raise ParseError((linenum, ERR_UNKNOWN, e))
+                raise ParseError(linenum, ERR_UNKNOWN, e)
             if ts <= last_timestamp:
-                raise ParseError((linenum, ERR_NON_MONOTONIC, ts))
+                raise ParseError(linenum, ERR_NON_MONOTONIC, ts)
             last_timestamp = ts
             if ts < start or ts >= end:
-                raise ParseError((linenum, ERR_OUT_OF_INTERVAL, ts))
+                raise ParseError(linenum, ERR_OUT_OF_INTERVAL, ts)
             self.append_iter(1, [row])
             written += 1
         return (written, indata.tell(), last_timestamp, linenum)