Upgrade to gulp v4, npm v8, node v16

Upgraded gulp to version 4
- gulp v3 has issues with recent versions of node, so I've upgraded to gulp v4 which supports the latest version of node.
- Upgrading required using gulp.serial() and gulp.parallel()
- I also had to move "build" task higher in the file because the new gulp version requires referenced tasks to be defined before they're referenced
- I also had to upgrade gulp-cache to get it to work
- Note that there are some style changes that were added automatically by husky (pretty-quick --staged") when I committed the change.
Generated the package-lock.json by using npm verson 8. The latest version of npm has a new, different format for the lockfile (lockfileVersion 2)
Upgraded husky, since npx husky install wasn't working
Ran npm audit fix to automatically fix any vulnerabilities that could be fixed without any breaking changes

Tour-360 / tour-player