With lots of tests and at least one `setTimeout`, completes early in an error state

When I tested on a single file, tap-dev-tool was working fine, but as soon as I loaded up a number of tests and put `setTimeout` in one of them, tap-dev-tool won't read tests properly past that point.

This is the output in the console when this occurs:
```
Failing Tests: 0

⨯ not ok
total: null
passing: 0
failing: 0
duration: 56 ms
ok 54 Timer started
ok 55 End time occurs after start time

1..55
# tests 55
# pass 55

# ok
```

I have confirmed when tap-dev-tool is disabled, the same issue does not occur. I'm using tape-catch through Webpack so that might have something to do with it. When running using tap-spec via PhantomJS, this issue also does not occur.