return true/false on attempt to invalidate module

[t1m0thy-michael]

invalidateByExports, invalidateByPath, prototype.invalidate to return true if module invalidable, otherwise false

Project using this want to log when a module is refreshed. This allows change allows

if (module.invalidateByPath(require_path)){ app.log.info(module refreshed: ${require_path}) obj.fn = require(require_path) }