test_rpc: Use numbers.Integral instead of long type
test_rpc: Use numbers.Integral instead of long type

Currently, test_rpc.py uses long type for PyPy interpreter compatibility,
but log type is obsoleted in Python 3.
This patch fixes test_rpc.py to use numbers.Integral and makes its
implemetation more clean.

Signed-off-by: IWASE Yusuke <bb80e84cc9f5a8f01385872ee89032beb5d4eba7@gmail.com>
Signed-off-by: FUJITA Tomonori <93dac1fe9c4b2a3957982200319981492ad4976e@lab.ntt.co.jp>

gareging/SDN_Framework,lagopus/ryu-lagopus-ext,pichuang/ryu,osrg/ryu,gareging/SDN_Framework,fujita/ryu,lagopus/ryu-lagopus-ext,gareging/SDN_Framework,osrg/ryu,pichuang/ryu,shinpeimuraoka/ryu,osrg/ryu,iwaseyusuke/ryu,pichuang/ryu,shinpeimuraoka/ryu,fujita/ryu,iwaseyusuke/ryu,lagopus/ryu-lagopus-ext,gareging/SDN_Framework,shinpeimuraoka/ryu,osrg/ryu,pichuang/ryu,lagopus/ryu-lagopus-ext,osrg/ryu,pichuang/ryu,iwaseyusuke/ryu,fujita/ryu,gareging/SDN_Framework,fujita/ryu,iwaseyusuke/ryu,fujita/ryu,iwaseyusuke/ryu,shinpeimuraoka/ryu,lagopus/ryu-lagopus-ext,shinpeimuraoka/ryu