[WIP]Add test module to Gluon-Face

[PistonY]

I'm going to write a test module and create CI. Any suggestions could write below.

[PistonY]

For now, I want to use Gluon-cv style to write our test module but will use pytest as test runner. CI maybe use Jenkins+Github cause we need test our datasets and dataloader. The following module are planning to test.

basic_block
datasets
dataloader
loss func
metrics
model zoo

This would cost one or two week.

[haoxintong]

I still want to use Green as unittest runner :D

[PistonY]

It's almost same thing. /dog