ExporterConfig refactorization (#2157)
* add type checking
* tflite config exporters
* add exporters config
* fix style
* fix
* fix
* remove constant
* fix style
* move
* rm comments
* fix masked-im output names
* style
* rm comment
* fix doc generation
* task attribute already set
* model patcher
* add model patcher
* add processor
* move patching specs to onnx config
* rename
* add comment
* fix
* style
* rename
* style
* remove todo comments
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Co-authored-by: IlyasMoutawwakil <moutawwakil.ilyas.tsi@gmail.com>