Bump webpack from 3.8.1 to 3.10.0

Bumps [webpack](https://github.com/webpack/webpack) from 3.8.1 to 3.10.0.
- [Release notes](https://github.com/webpack/webpack/releases?after=v4.0.0-alpha.0)
- [Commits](https://github.com/webpack/webpack/compare/v3.8.1...v3.10.0)