Added support for parsing out the timestamp

The timestamp is in the LOG module, at an offset of either 465 or
469. There is no obvious marker for which files have it at 465 and
which at 469.

BioLogic.py

@@ -7,7 +7,7 @@ import re
 import csv
 from os import SEEK_SET, SEEK_CUR
 import time
-from datetime import date
+from datetime import date, datetime, timedelta
 from collections import OrderedDict
 from warnings import warn
 
@@ -261,3 +261,24 @@ class MPRfile:
             tm = time.strptime(str(log_module['date'],  encoding='ascii'),
                                '%m/%d/%y')
             self.enddate = date(tm.tm_year, tm.tm_mon, tm.tm_mday)
+
+            ## There is a timestamp at either 465 or 469 bytes
+            ## I can't find any reason why it is one or the other in any
+            ## given file
+            ole_timestamp1 = np.fromstring(log_module['data'][465:],
+                                           dtype='<f8', count=1)
+            ole_timestamp2 = np.fromstring(log_module['data'][469:],
+                                           dtype='<f8', count=1)
+            if ole_timestamp1 > 40000 and ole_timestamp1 < 50000:
+                ole_timestamp = ole_timestamp1
+            elif ole_timestamp2 > 40000 and ole_timestamp2 < 50000:
+                ole_timestamp = ole_timestamp2
+
+            ole_base = datetime(1899, 12, 30, tzinfo=None)
+            ole_timedelta = timedelta(days=ole_timestamp[0])
+            self.timestamp = ole_base + ole_timedelta
+            if self.startdate != self.timestamp.date():
+                raise ValueError("""Date mismatch:
+                Start date: %s
+                End date: %s
+                Timestamp: %s""" % (self.startdate, self.enddate, self.timestamp))