Closes #259: Adds new lint items_before_use

[utkrsharmaa]

fixes #259
changelog: New lint [items_before_use]: Checks for misplaced use statements at module level.

Has a configurable strict mode which enforces to group use statements above all other items in module for better code organization and readability.

Both default and strict mode ignore use statements in cfg blocks.

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  • 38810df

[utkrsharmaa]

Was missing one allow statement for my lint in an internal lint. added it just now. Apologies.