issue #104: undefined function 'extended_to_double' has been replaced by plain float/double conversion for default case (with test_elphyio rerun)

$ workon neo
(neo):iotest$ python test_elphyio.py 
.....
----------------------------------------------------------------------
Ran 5 tests in 4.688s

OK
Merge pull request #106 from dguarino/patch-1

issue #104: undefined function 'extended_to_double' has been replaced by...