BUG - PeriodIndex.freq.normalize option gets cached per process
It seems that whatever normalize option is first called for a PeriodIndex freq it is used for the rest of the process (on a per offset type basis). No matter whether the freq is explicitly overwritten with a freq using a different normalize option. This is NOT the case for the offset kwds.

    >>> pd.PeriodIndex(['19910905'], freq=pd.offsets.YearEnd(normalize=True)).freq.normalize
    True
    >>> pd.PeriodIndex(['19910905'], freq=pd.offsets.YearEnd(normalize=False)).freq.normalize
    True

Restart the process

    >>> pd.PeriodIndex(['19910905'], freq=pd.offsets.YearEnd(normalize=False)).freq.normalize
    False
    >>> pd.PeriodIndex(['19910905'], freq=pd.offsets.YearEnd(normalize=True)).freq.normalize
    False

