Devtools patch

[mdtusz]

Fixes #404 and improves perceived search performance.

• Set interval check to run onReload function only after the new plotly.js bundle has loaded.
• Debounce the fuzzy search for mocks by 250ms.

[etpinard]

@mdtusz Pardon my ignorance: why do we need to debounce the fuzzy search?

[mdtusz]

The search was being run on every keyup before - on my machine that blocks things and is surprisingly slow. We could also just run the search when there's an enter keypress if you'd prefer.

[etpinard]

@mdtusz thanks. 💃

This looks good. I don't see the need to implement an <enter> handle.