Additional Cache key significant properties

[ivansky]

Add additional Cache significant properties from context like server extraCacheKeyData.

Use Case:
There are at least two properties that are sent by headers and receive different data from GraphQL Server:

1. Language
2. Device type (mobile / desktop)

Example of usage:
It needs to add somehow to cache lifecycle additional properties that affect cache data.
Something like:

someCacheKeyExtendPlugin({
  language: (context) => context.language,
  deviceType: (context) => context.deviceType,
})

or

someCacheKeyExtendPlugin((context) => {
  language: context.language,
  deviceType: context.deviceType,
})

Then if user change language, the data should be reloaded and show some sign of loading for UX.

[ghost]

+1