add titleFormatter property type definition for ReduxLoggerOptions

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• Use a meaningful title for the pull request. Include the name of the package modified.
• Test the change in your own code. (Compile and run.)
• Add or edit tests to reflect the change. (Run with npm test.)
• Follow the advice from the readme.
• Avoid common mistakes.
• Run npm run lint package-name (or tsc if no tslint.json is present).

Select one of these and delete the others:

If adding a new definition:

• The package does not already provide its own types, or cannot have its .d.ts files generated via --declaration
• If this is for an NPM package, match the name. If not, do not conflict with the name of an NPM package.
• Create it with dts-gen --dt, not by basing it on an existing project.
• tslint.json should be present, and tsconfig.json should have noImplicitAny, noImplicitThis, strictNullChecks, and strictFunctionTypes set to true.

If changing an existing definition:

• Provide a URL to documentation or source code which provides context for the suggested changes: <>
• Increase the version number in the header if appropriate.
• If you are making substantial changes, consider adding a tslint.json containing { "extends": "dtslint/dt.json" }.

If removing a declaration:

• If a package was never on DefinitelyTyped, you don't need to do anything. (If you wrote a package and provided types, you don't need to register it with us.)
• Delete the package's directory.
• Add it to notNeededPackages.json.