fixed windows newline support

Author: wolph

stl/stl.py

@@ -143,8 +143,6 @@ def _ascii_reader(cls, fh, header):
             line_separator = b'\r\n'
         elif b'\n' in header:
             pass
-        elif b'\r' in header:
-            line_separator = b'\r'
         else:
             recoverable = [False]
             header += b(fh.read(BUFFER_SIZE))