BUG when start dt is a monday:

Monday to Sunday

>>> from xix.utils.timetool import setDayOfWeek, SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY
>>> from time import strptime, strftime, mktime, tzset
>>> from datetime import datetime
>>> t = strptime('2005-11-28', '%Y-%m-%d')
>>> dt = datetime.fromtimestamp(mktime(t))
>>> dt2 = setDayOfWeek(dt, SUNDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-12-04


Monday to Monday:

>>> dt2 = setDayOfWeek(dt, MONDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-11-28


Monday to Tuesday

>>> dt2 = setDayOfWeek(dt, TUESDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-11-29


Monday to Wednesday

>>> dt2 = setDayOfWeek(dt, WEDNESDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-11-30

Monday to Thursday


>>> dt2 = setDayOfWeek(dt, THURSDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-12-01

Monday to Friday


>>> dt2 = setDayOfWeek(dt, FRIDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-12-02

Monday to Saturday

>>> dt2 = setDayOfWeek(dt, SATURDAY)
>>> print strftime('%Y-%m-%d', dt2.timetuple())
2005-12-03


