TYP: enable strict_equality to prohibit comparisons of non-overlappin…
…g types

By default, mypy allows always-false comparisons like 42 == 'no'. Use this flag to prohibit such comparisons of non-overlapping types, and similar identity and container checks
```
pandas\core\dtypes\base.py:239: error: Non-overlapping equality check (left operand type: "str", right operand type: "Callable[[ExtensionDtype], str]")      
pandas\core\arrays\period.py:657: error: Non-overlapping container check (element type: "Callable[[Any], Any]", container item type: "Callable[[Any, Any], Any]")
pandas\core\arrays\period.py:658: error: Non-overlapping identity check (left operand type: "Callable[[Any], Any]", right operand type: "Callable[[Any, Any], Any]")
pandas\io\formats\format.py:307: error: Non-overlapping equality check (left operand type: "bool", right operand type: "Literal['truncate']")
pandas\io\formats\format.py:461: error: Non-overlapping equality check (left operand type: "bool", right operand type: "Literal['truncate']")
pandas\io\excel\_odfreader.py:159: error: Non-overlapping equality check (left operand type: "str", right operand type: "float")
```
thanks @simonjayhawkins  Master seems to be failing now with `pandas/core/generic.py:464: error: Non-overlapping identity check (left operand type: "str", right operand type: "Type[int]")` which I think might be a result of this. Giving it a look