Resolve namespace package

[ifeitao]

imp.find_module can't find namespace package, update to importlib to resolve package path

[coveralls]

Coverage decreased (-0.9%) to 95.538% when pulling 99e77af on yifeitao:resolve_namespace_package into 5c7e078 on chimpler:master.

[coveralls]

Coverage decreased (-0.9%) to 95.538% when pulling 99e77af on yifeitao:resolve_namespace_package into 5c7e078 on chimpler:master.

[coveralls]

Coverage decreased (-0.9%) to 95.538% when pulling 99e77af on yifeitao:resolve_namespace_package into 5c7e078 on chimpler:master.

[coveralls]

Coverage decreased (-0.9%) to 95.538% when pulling 99e77af on yifeitao:resolve_namespace_package into 5c7e078 on chimpler:master.

[coveralls]

Coverage decreased (-0.9%) to 95.538% when pulling 99e77af on yifeitao:resolve_namespace_package into 5c7e078 on chimpler:master.

[coveralls]

Coverage decreased (-0.08%) to 96.154% when pulling e2b0e1f on yifeitao:resolve_namespace_package into 5d08816 on chimpler:master.

[darthbear]

Thank you @yifeitao!