Use Command line options instead of positional arguments when launching spark applications from various CLI commands

Hoodie CLI commands like compaction/rollback/repair/savepoints/parquet-import relies on launching a spark application to perform their operations (look at SparkMain.java). 

SparkMain (Look at SparkMain.main()) relies on positional arguments for passing  various CLI options. Instead we should define proper CLI options in SparkMain and use them (using Jcommander)  to improve readability and avoid accidental errors at call sites. For e.g : See com.uber.hoodie.utilities.HoodieCompactor

## JIRA info

- Link: https://issues.apache.org/jira/browse/HUDI-96
- Type: Task
- Epic: https://issues.apache.org/jira/browse/HUDI-1388

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## Comments

04/May/19 17:07;abhioncbr;Since some of the commands in SparkMain.java are invoking methods of different classes which already have Jcommander configs. To make all of them easy to use, I am thinking to have a package in sub-project `hoodie-common` say `com.uber.hoodie.common.jobConfigs` which will have configs classes of all the Main launcher classes. It will help us to consolidate job configs and make them easy to manage. 

[~vbalaji], please share your thoughts on my approach.;;;

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04/May/19 20:29;abhioncbr;Also, if pursuing the above approach is it ok to mention class name as a string for example 'com.uber.hoodie.utilities.sources.JsonDFSSource';;;

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11/May/19 21:56;abhioncbr;PR raise https://github.com/apache/incubator-hudi/pull/673;;;

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08/Aug/19 04:15;vinoth;[~abhioncbr] are you still working on this patch? ;;;

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30/Aug/19 16:20;vinoth;Moving ticket back to opened due to inactivity;;;

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03/Jan/20 11:12;Pratyaksh;[~vbalaji] I have resumed the work for this ticket and have tried to address most of the comments that you already gave. I have raised a fresh PR for this. Please have a look and let me know your thoughts. Here is the PR - [https://github.com/apache/incubator-hudi/pull/1174].;;;

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07/Sep/21 21:07;githubbot;vinothchandar closed pull request #1174:
URL: https://github.com/apache/hudi/pull/1174

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07/Sep/21 21:07;githubbot;vinothchandar commented on pull request #1174:
URL: https://github.com/apache/hudi/pull/1174#issuecomment-914630077

Closing due to inactivty

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Start with SparkMain.java and SparkMain.main(), then inspect the HoodieCompactor call site and the other CLI commands named in the issue. Trace how positional arguments are passed into the Spark application and identify the existing Jcommander configurations. Done means those launchers use named CLI options consistently without breaking compaction, rollback, repair, savepoint, or parquet-import operations.

Written by the indexing model from the issue text.