statistics menu leveling to improve user experience

[oscar-escire]

References

Add references/links to any related issues or PRs. These may include:

• Fixes UX statistics links behavior is not consistent with the header behavior #1392

Description

This PR changes the statistics button to a menu with sublevels that, depending on where the user is, shows you more or fewer options.

Instructions for Reviewers

List of changes in this PR:

• Changed statistics button on main bar to a menu with sublevels.
• Enabled different subleveles depending where the user is:
  ** To main page allow view main statistics
  ** To community page allow view main statistics and selected community statistics
  ** To collection page allow view main statistics, selected community statistics and selected collection statistics
  ** To collection page allow view main statistics, selected community statistics, selected collection statistics and item selected item statistics

To check this PR:

1. Over main page you will see the statistics menu, if you pass mouse over it, you will see the statistics allowed options.
2. A similar behavior will work over community, collection or item page but the allowed options will change when you get deeper on the repo structure

Checklist

• My PR is created against the main branch of code (unless it is a backport or is fixing an issue specific to an older branch).
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