Fixing the issue with reading fullSEED files.

Now all fullSEED files should be read correctly. The issue was that the
first data record in fullSEED files previously must have had the
dataquality D. Now all valid dataqualities are allowed.

obspy/mseed/util.py

@@ -302,7 +302,7 @@ def _getRecordInformation(file_object, offset=0):
         # reset file pointer
         file_object.seek(record_start, 0)
         # cycle through file using record length until first data record found
-        while file_object.read(7)[6] != 'D':
+        while file_object.read(7)[6] not in ['D', 'R', 'Q', 'M']:
             record_start += rec_len
             file_object.seek(record_start, 0)