Revert Virtual Time related references
Revert Virtual Time related references

matthewhampton/python-datetime-tz,davidfraser/python-datetime-tz,j5int/python-datetime-tz,j5int/python-datetime-tz,mithro/python-datetime-tz,mithro/python-datetime-tz,davidfraser/python-datetime-tz,dave42/python-datetime-tz