Handle array of types in isOfType

[paszkowskiDamian]

It is PR implementing new API proposed in issue #85. API of isOfType has been extended to accept also an array of types as redux-observable operator ofType. It does not introduce any baking changes.

• Rebase before creating a PR to keep commit history clean
• Clear node_modules and reinstall all the dependencies: npm run reinstall
• Run checker npm script: npm run check

Extra checklist:

• Always add some description and refer to all the related issues using # tag

For bugfixes:

• Add at least one unit test to cover the bug that have been fixed

For new feature:

• Update API docs
• Add examples to demonstrate new feature
• Add type unit tests
• Add runtime unit tests