New functionality: Update translations

[jhholm]

This pull request contains the following changes

• Adds crossenv to support development in Windows
• Moved @types dependencies to devDependencies
• Added dependencies that are used, but not mentioned in package.json - makes this work with pnpm if needed
• Fixes popup to work in incognito and private browser - wrapped fetch calls in chrome.scripting.executescript
  • Actions pivot used to be grayed out when in incognito
• New functionality - update translations for a site page

There is a bug within SharePoint that I've had to use PnP JS console to fix for a long time. Technically it's possible that the data in search, item level and translations api can get out of sync, and you get duplicated entries in news web parts on translated pages. Checked that the Translations functionality in SharePoint itself uses this same API from time to time if do you happen funny stuff.