BUG: open csvfile with newline='' on Python 3

See http://docs.python.org/3/library/csv.html#csv.writer:
```
If newline='' is not specified, newlines embedded inside quoted fields will not 
be interpreted correctly, and on platforms that use \r\n linendings on write an 
extra \r will be added. It should always be safe to specify newline='', since the 
csv module does its own (universal) newline handling.
```

Fixes one test error on Python 3.x on Windows:
```
======================================================================
ERROR: Failure: IndexError (pop from empty list)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "X:\Python32\lib\site-packages\nose\failure.py", line 38, in runTest
    raise self.exc_val.with_traceback(self.tb)
  File "X:\Python32\lib\site-packages\nose\loader.py", line 254, in generate
    for test in g():
  File "X:\Python32\lib\site-packages\la\tests\deflarry_creation_test.py", line 95, in test_conversion
    y2 = larry.fromcsv(filename)
  File "X:\Python32\lib\site-packages\la\deflarry.py", line 4825, in fromcsv
    return larry.fromtuples(data)
  File "X:\Python32\lib\site-packages\la\deflarry.py", line 4554, in fromtuples
    xs = labels.pop(-1)
IndexError: pop from empty list
```