Implement Rollback like API in HoodieWriteClient which can revert all actions

Related to HUDI-716 and PR-1432

The PR address the specific issue of deleting orphaned inflight/requested clean actions by older versions of Hudi. 

Currently rollback performs reverting only commit and delta-commit operations. We can introduce a new API which will consistently revert all pending actions clean, compact, commit  and delta-commit.  Currently, we dont rollback clean. Instead we expect future clean operations to first finish up pending clean first. By having this new API (rollbackPendingActions), we can let users consistently revert any actions if they want.

## JIRA info

- Link: https://issues.apache.org/jira/browse/HUDI-747
- Type: New Feature
- Affects version(s):
- 0.9.0
- Fix version(s):
- 1.1.0

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## Comments

30/Mar/20 09:14;vbalaji;[~lamber-ken] FYI. If you are interested, kindly go through this ticket and take it up. 

Thanks,

Balaji.V;;;