Keep test case and ci updated when developing

[yanganto]

The test and ci are also parts of the development.
There is no KTON test case in the current develop branch and the Staking test case is reverted.

• The .maintain/ci/darwinia_test_script.sh should be updated with Refactoring Balances #307 merged.
• The staking test case should be kept in passed without comment when Upgrade to Substrate-Alpha.3 #312 merged, this also revert the work of Test/staking #293.

[clearloop]

Well, I'm trying to fix treasury's tests now.

[aurexav]

We don’t need the KTON tests. Those two module use the same code.

[clearloop]

We don’t need the KTON tests. Those two modules use the same code.

I realized it this afternoon, I'll keep some functional tests with KTON parallel in treasury's tests, and delete most of them.