Error handling is broken

[resignationinfinite]

Upon running the tool, I get the following response:

> omnivore-import-demo@1.0.0 import
> npx babel-node -x .ts index.ts

Connecting to  https://api-prod.omnivore.app/api/graphql
error response: [object Object]
Successfully started import.

This is problematic both due to the unspecific error response, as well as the fact that the tool reports a successful import regardless of anything (the success message should presumably instead be included in the try block).

[tdhooten]

I have created PR #5 to fix this issue.