pre-commit script: doctoc.js could not be found

* `kcd-scripts` version: 0.37.0
because of the potential breaking change in 0.38, I decided not to upgrade
* `node` version: 0.8.4
* `npm` version: 0.5.3
* `windows` version: 10

### What you did:

While working on the PR for `cypress-testing-library`, I thought I'd enable the pre-commit hook. So I added the `.opt-in` file and added the `pre-commit` text to it. Then I did the git commit (both SourceTree and command line)

### What happened:

```
Running tasks for README.md [started]
Running tasks for README.md [failed]
→ .\node_modules\doctoc\doctoc.js could not be found. Try `npm install .\node_modules\doctoc\doctoc.js`.
```
`doctoc.js` does exist in the node_modules folder.

Reproduce the pre-commit run using the `.opt-in` file and `README.md`, then inspect how the hook resolves `node_modules/doctoc/doctoc.js`. Confirm the behavior with the reported kcd-scripts, Node, npm, and Windows versions; done means the pre-commit task completes without the missing-file error.

Written by the indexing model from the issue text.