drainTimeout is not used in WaitForTermination

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Is this a BUG REPORT or FEATURE REQUEST?:
Bug
What happened:
use case I observed:

1. rollingUpgrade has drainTimeout configured (7 mins)
2. postDrain helper script fails.
3. drainTimeout specifies Node will be terminated after drain timeout even if kubectl drain has not been completed
4. WaitForTermination ignores DrainTimeout and uses const of 1h https://github.com/keikoproj/upgrade-manager/blob/master/controllers/rollingupgrade_controller.go#L270-L273

What you expected to happen:
If drain timeout is configured, then wait for termination should use it OR provide another field in spec to configure the timeout.