BUG: Resample across multiple days
Fixes an issue where resampling over multiple days causes a ValueError
when a number of days between the normalized first and normalized last
days is not a multiple of the frequency.

Added test TestSeries.test_resample

Closes #8683

@hkleynhans I think test_resample.py is a better place to put the test (https://github.com/hkleynhans/pandas/blob/fix/8683_resample_value_error/pandas/tseries/tests/test_resample.py)
 Thanks for the feedback.  The issues have been addressed.
 @jreback can you have a look at this? (or is there someone with great knowledge of the resample code?) But the change seems logic, and the tests pass
 will have a look
 looks good.

@jorisvandenbossche merge on green.
 @hkleynhans Thanks a lot! It was nice debugging
