API: DatetimeIndex.to_julian_date now returns a
     Float64Index.
TST: Moved to_julian_date tests from
     pandas/tseries/tests/test_julian_date.py into
     pandas/tseries/tests/test_timeseries.py
DOC: Added mention of to_julian_date functionality
     to doc/source/release.rst and v0.14.0.txt