Friendly error message when calling interactor with non-hash arguments

[taylorthurlow]

This is from my own issue (collectiveidea/interactor#178) on the Interactor repo.

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If I call an interactor like so:

MyInteractor.call(something)

rather than the correct:

MyInteractor.call(something: "something")

Then I get a semi-cryptic error like:

NoMethodError:
       undefined method `each_pair' for #<MyInteractor:0x00007fa2fc407350>

It's pretty easy to see that I just called the interactor incorrectly, but it seems like it would be easy to check the provided parameters and raise a helpful error.