Update for Flarum v1

[imorland]

• After merging a previously split discussion, the modal remains open, and this is added to the destination discussion

• Using merge into me, the merge modal remains open after the merge completes, rather than returning to the discussion

• Merged discussions are not removed from the discussion list after successful merge, if merged from within a discussion

[dsevillamartin]

After merging a previously split discussion, the modal remains open, and this is added to the destination discussion

This will happen regardless of if split was used or not - e.g. if the issue with modal not closing happens and you click merge multiple times.

Using merge into me, the merge modal remains open after the merge completes, rather than returning to the discussion

Had this happen but thought it was because I had changed something in the JS - I see now that was not the issue.

[dsevillamartin]

Merged discussions are not removed from the discussion list after successful merge, if merged from within a discussion

I could not reproduce this.

I think I have fixed the other errors I found, however.

[Ralkage]

Just tested and haven't experienced any of the issues mentioned even after the recent changes @datitisev made; I believe we are good to merge this.

[dsevillamartin]

Nooo by debug console.log()s have leaked 😂