feat(context-menu): new sheet experiment

[linhnguyen-qlik]

Motivation

Expose the getContextMenu function so we could use it in QmfeEmbed. This function take features as one of it's parameter and return a list of features that might have been modified by the chart.

Question:

• Should we called it something else to differentiate between the new and old one?

Requirements checklist

• Api specification
  • Ran yarn spec
    • No changes OR API changes has been formally approved
• Unit/Component test coverage
• Correct PR title for the changes (fix, chore, feat)

When build and tests have passed:

• Add code reviewers, for example @qlik-oss/nebula-core