Add version check for self-hosted discussion settings

[kwonye]

Current versions of WordPress self-hosted do not have the discussion settings triggers in place. Version-check before showing discussion settings on self-hosted sites.

[tonyr59h]

Just pinged for an update to the issue here.. Once I get the info I'll add the feature toggle.

[kwonye]

Update: WordPress 4.5 will likely have this. Older self-hosted versions will maintain the "old" settings (#3562) while the new 4.5 would have the new settings

[maxme]

Still no news from the WordPress ticket.

[stale]

This issue has been marked as stale and will be automatically closed. This happened because:

• It has been inactive for the past year.
• It isn't in a project or a milestone.
• It hasn’t been labeled `[Pri] Blocker`, `[Pri] High`, or `good first issue`.

However, discussion is still welcome! If the issue is still valid, please leave a comment with a brief explanation so the issue can be reopened.