Added Hindi Aggressive Tokenizer

[MukeshSinghBisht]

Hindi Language aggressive tokenizer.

• Added Hindi Language aggressive tokenizer which considers language specific symbols to be swallowed.
• And to test them added several test cases as well.
  I request fellow maintainers and contributors to review and merge my PR or raise queries or suggest changes.
  I would highly appreciate inputs.
  Thanks in Advance.

[Hugo-ter-Doest]

Please restrict the copyright notice to the file you authored. Now it says that you authored the aggressive tokenizer as a whole. Also remove the line with "Aggressive Tokenization Open-Source License (Version 1.0)" That is not an actually existing license. We are using MIT license.

Otherwise your license text is compatible with MIT license.

[MukeshSinghBisht]

Please restrict the copyright notice to the file you authored. Now it says that you authored the aggressive tokenizer as a whole. Also remove the line with "Aggressive Tokenization Open-Source License (Version 1.0)" That is not an actually existing license. We are using MIT license.

Otherwise your license text is compatible with MIT license.

Thanks @Hugo-ter-Doest for your inputs,
I made the the changes regarding license text. Please refer commit: 735295c

[coveralls]

Pull Request Test Coverage Report for Build 5983185211

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 40 of 40 (100.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.04%) to 87.331%

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Totals
Change from base Build 5965872452:	0.04%
Covered Lines:	9661
Relevant Lines:	10691

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💛 - Coveralls

[Hugo-ter-Doest]

Thanks for your contribution! Very nice to have a Hindi tokenizer as part of the natural library.

[MukeshSinghBisht]

Welcome ! I will try adding more contributions ahead.

[Hugo-ter-Doest]

FYI I added the Hindi tokenizer to the API (index.js and index.d.ts files) and added it to the documentation at https://naturalnode.github.io/natural/