Support waitForFinish() in remote and add duration to both

WE need the consistent api for waitForFinish() in remote runner. This is for two reasons:

1. feature parity with local runner
2. for future use case if we support submit a batch job to a remote cluster and allow user program to wait till it completes to check the output.

We need another variant of waitForFinish(duration). This is to be compatible with BEAM API.