Intelelm

+ Add supported information for each classes.
+ Restructure intelelm module to based_elm module and model subpackage that includes mha_elm and standard_elm modules.
+ Add traditional/standard ELM models (ElmRegressor and ElmClassifier classes) to standard_elm module.
+ Add examples and tests for traditional models
+ Add score and scores functions to all classes.
+ Fix bug calculate metrics and objective in ELM-based models.
+ Add examples with real-world datasets and examples with GridsearchCV to tune hyper-parameters of ELM-based models.
+ Add documents

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+ Add infors (CODE_OF_CONDUCT.md, MANIFEST.in, LICENSE, README.md, requirements.txt, CITATION.cff)
+ Add supported classification and regression datasets
+ Add util modules (data_loader, validator, evaluator, encoder, activation)
+ Add MhaElmRegressor and MhaElmClassifier classes
+ Add publish workflows
+ Add examples and tests folders