using readlines() in _tsv.py fixes a small bug. 

The current documentation gives an example that causes an error, because its using \n for line endings. The error message suggested that I should be using universal line endings, but the function was using split('\r\n').  I changed it to use readlines()  and that seems to clear it up. I only tested in python 2.7 on linux. 

Documentation I was referring to:

data = tablib.Dataset()
data.tsv = 'age     first_name      last_name\n90   John    Adams'