python: keep consistent handling of Python integer conversion

python: keep consistent handling of Python integer conversion

libvirt_ulonglongUnwrap requires the integer type of python obj.
But libvirt_longlongUnwrap still could handle python obj of
Pyfloat_type which causes the float value to be rounded up
to an integer.

For example
 >>> dom.setSchedulerParameters({'vcpu_quota': 0.88})
 0
libvirt_longlongUnwrap treats 0.88 as a valid value 0

However
 >>> dom.setSchedulerParameters({'cpu_shares': 1000.22})
libvirt_ulonglongUnwrap will throw out an error
"TypeError: an integer is required"

The patch make this consistent.