Bnunicodenormalizer

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- base normalizer
- language class
- bangla extension
- complex root normalization

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- MultipleConsonantDiacritics handling change
- to+hosonto correction
- invalid hosonto correction

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- assemese replacement
- word op and unicode op mapping
- modifier list modification
- doc string for call and initialization
- verbosity removal
- typo correction for operation
- unit test updates
- 'এ' replacement correction
- NonGylphUnicodes
- Legacy symbols option
- legacy mapper added
- added bn:bd declaration

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- broken diacritics op addition

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- added details for execution map
- checkop typo correction