flow-runtime-cli doesn't output type aliases

This is a:

- [ ] Bug Report
- [ ] Feature Request
- [X] Question
- [ ] Other

Which concerns:

- [X] flow-runtime
- [ ] babel-plugin-flow-runtime
- [ ] flow-runtime-validators
- [ ] flow-runtime-mobx
- [ ] flow-config-parser
- [ ] The documentation website

---

### What is the current behaviour?

(This is similar to #69 but, TBH, I don't understand what the problem was and `flow-runtime-cli` didn't produce any output for me. If there are some docs that describe what's happening, please point me in the right direction.)

When running the following code:

```
import axios from 'axios';
import type {AxiosPromise} from 'axios';

const request: AxiosPromise = axios.get('https://google.com/');
```

...this message is printed to the console:

> flow-runtime: Failed to reveal unknown type in Temporal Dead Zone.

Can you help me understand what this means and what the right fix is?

---

### What is the expected behaviour?

No message appears.

---

### Which package versions are you using?

```
{
"dependencies": {
"axios": "^0.16.1",
"babel-cli": "^6.24.1",
"babel-plugin-flow-runtime": "^0.11.1",
"babel-plugin-transform-decorators-legacy": "^1.3.4",
"babel-preset-react": "^6.24.1",
"babel-preset-stage-2": "^6.24.1",
"flow-bin": "^0.47.0",
"flow-runtime": "^0.12.0",
"flow-runtime-cli": "^0.12.0",
"flow-typed": "^2.1.2"
}
}
```