Custom branding (II)

[gdiazlo]

We want to be able to customize some parts of the dashboard experience, so our community can tailor the experience for their users.

• Remove Wazuh wording from the health check page

• Remove duplicated help entries

• Customize icons / text on the left menu

• Customize logo and color in the login screen

• Customize loading page logo

We need to this to be configurable in our configuration files and from the user interface / API.
Also, we should explore CSS options enabling the interface to update dynamically.

We must consider the work being done already in opensearch:

https://github.com/opensearch-project/OpenSearch-Dashboards/issues?q=is:issue+is:open+branding

If our solution could benefit all opensearch community, we should open a PR in their repository, and try to incorporate the changes into the upstream.