MAINT: Read text in Python 3 instead of bytes when fetching public data.

Account for byte/string compatibility when consuming response from
requests module.

zipline/data/benchmarks.py

@@ -88,7 +88,7 @@ start_date={start_date}, end_date={end_date}, url={url}""".strip().
                                                 end_date=end_date,
                                                 url=res.url))
 
-    return csv.DictReader(res.iter_lines())
+    return csv.DictReader(res.text.splitlines())
 
 
 def get_benchmark_data(symbol, start_date=None, end_date=None):

zipline/data/treasuries.py

@@ -98,7 +98,7 @@ def get_treasury_source():
 http://data.treasury.gov/feed.svc/DailyTreasuryYieldCurveRateData\
 """
     res = requests.get(url, stream=True)
-    stream = iter_to_stream(res.iter_lines())
+    stream = iter_to_stream(res.text.splitlines())
 
     elements = ET.iterparse(stream, ('end', 'start-ns', 'end-ns'))