Cleanup/Improve the messages entries of the audit search element

Since NXP-28863 the audit admin and the audit document share the same element the nuxeo-audit-search. This way it's more easy to improve the audit and so on. But we find ourselves with a different entries for the columns labels like: Activity.Key, eventType.Key, categoryType.Key
the eventType.Key, categoryType.Key was the audit ones
and Activity.Key the document history one. Since NXP-28863 We use mainly the activity one and we add the missing ones from the audit. The purpose of this new ticket is to make things more consistent:

• Separate Keys between Event Type and Categories
• Try to make the values consistent: Should be Capitalised (first letter)
• Keep only the used ones, for now the below are used in retention:
  "documentHistory.date": "Date",
  "documentHistory.filter.after": "After",
  "documentHistory.filter.before": "Before",
  "documentHistory.username": "Username",

• Add translations for nuxeo-document-history (as seen below, copy existing values from nuxeo-audit into the corresponding filter values)

  audit.username -- copy to --> documentHistory.filter.username
  audit.usernamePlaceholder -- copy to --> documentHistory.filter.usernamePlaceholder
  audit.eventType -- copy to --> documentHistory.filter.eventType
  audit.selectEventTypes -- copy to --> documentHistory.filter.selectEventTypes
  audit.eventCategory -- copy to --> documentHistory.filter.eventCategory
  audit.selectEventCategory -- copy to --> documentHistory.filter.selectEventCategory 

   

We should also take chance to have a look at the consistency between what the backend sort and the labels used in UI (as we use a specific message which may not be the ones that the backend used to sort)