Sequence reader now ignores blank lines

mrdna/model/dna_sequence.py

@@ -6,7 +6,7 @@ def read_sequence_file(sequenceFile=_m13_path):
     with open(sequenceFile) as ch:
         for l in ch:
             l = l.strip().replace(" ", "")
-            if l[0] in (";","#"): continue
+            if len(l) == 0 or l[0] in (";","#"): continue
             seq.extend([c.upper() for c in l])
     return list(seq)