[DO NOT MERGE]Add full runv functional test(oci compatible)

[Crazykev]

Ref: #462
Now this test patch can basically run, Anyone want to test in your local environment, please follow the rules:

*PREPARE*
1. build and install runv to `/usr/local/bin/runv`
2. run `hack/ci-setup.sh` to setup necessary environment and tools.
*RUN TEST*
1. run `hack/functional-test.sh` to run test case 

While there is still some issues in runv that makes most cases failed, I'll open an issue(#481) to track them.

Signed-off-by: Crazykev crazykev@zju.edu.cn

[laijs]

@Crazykev tests/bats-integration was added, it contains more tests. thanks for adding this!

[WeiZhang555]

Aha...catch a typo, s/MERAGE/MERGE/ :wink:

[Crazykev]

@laijs Cool, so I need to close this now.
@WeiZhang555 after correct this typo in the title ;)