Support edit locking

[johnjamesjacoby]

WordPress Admin supports post locking, where only user is allowed to edit a post or page at a time. bbPress supports this within the context of wp-admin but it does not write the necessary meta-data when editing forums/topics/replies via a front-end, theme-side form.

This can lead to confusion if one user edits a topic via the theme, and another user edits a topic via wp-admin.

[johnjamesjacoby]

In 6341:

Moderation: Use the appropriate _edit_ post meta when editing a forum/topic/reply.

This first pass does not introduce any theme-side edit-locking interface, but it will warn any user within wp-admin if another user is editing something theme-side.

See #3073.

[johnjamesjacoby]

In r6344

Moderation: Implement theme-side edit-lock interface.

• Edits to defaut theme javascript to interact with alert UI
• Add alert-topic-lock.php template part
• Add topic functions relating to edit-lock functionality
• Modify single-topic and topic-edit template parts to include the alert part
• Add CSS to Default template pack to stylize edit-lock alert like a modal (could be pretty much anything)

Props pippin for inspiration. See #3074.

[johnjamesjacoby]

This isn't *exactly* like the moderator is viewing approach, at least not yet.

With the Heartbeat and user-relationships APIs, there is alot more we can do in regards to who is viewing what.

[netweb]

In 6348:

Moderation: CSS coding standards fixes follow up after [6344]

See #3073.

[netweb]

In 6349:

Moderation: Autoprefixer follow up to [6348] and [6344]

See #3073.

[netweb]

See also #3005 - Notification to moderators when administrative tasks are being carried out

[johnjamesjacoby]

Assigning all closed & unassigned tickets in the 2.6 milestone to myself.