Inconsistent vocabulary and ordering of the "autowatch" feature in the user notification preferences

This is about the autowatch configuration select, this one:

Vocabulary:

• It's not clear what "watching" means here, I think this is the only place where we use the "watch" action name on this screen
• The "watch" vocabulary is used in the tooltips of the switches that are displayed in the notifications menu under the bell icon
• The "watching" action (manual or automatic) is actually tightly related to the "Custom filters" table, that was added on the notification config screen as a separate item, by XWIKI-18406 . From a wording point of view, there is no explanation that they are almost one and the same thing.

Ordering:

• The autowatch feature is displayed above the system filters in the global configuration and above the event types in the user configuration, while it's strictly related to the Custom filters (added by XWIKI-18406 ). It should be displayed along with the Custom filters table, since it's concerning the same feature.