Potential improvements to abort task handling - tez/llap

Follow up from HIVE-14003.

• TezProcessor.run() - in case of an abort, throw an interrupt exception instead of falling off. (Falling off cleanly indicates success)
• Potential cleanup when initialize exits early
• MapRecordProcessor: MultiMRInput - waitForAllInputsReady can block if interrupts are swallowed elsewhere. Use changes from TEZ-3302.
• MapRecordProcessor: mergeMapOp handling - this will never be informed about an abort request
• MapRecordProcessor: Likewise, handling of dummyOp
• MapRecordProcessor: Abort handling in MergeFileRecordProcessor
• ReduceRecordProcessor: waitForAllInputsReady. Loop and timed wait after TEZ-3302
• ReduceRecordProcessor: dummyOp handling