feat: enable looping during next/prev

[jrnxf]

This PR accomplishes two goals:

1. Allow for looping through results in the Trouble buffer. The previous action on the first result will loop you to the last result, whereas the next action on the last result will loop you to the first.

Screen.Recording.2022-11-16.at.11.36.42.PM.mov

2. Exposes the is_open method. Useful for creating trouble-aware mappings. For example, I want <C-j> to open trouble if not already opened. If it is open, then have it take me to the next result like normal.

km.nnoremap('<C-j>', function()
  if not trouble.is_open() then
    trouble.open()
  else
    trouble.next({ skip_groups = true, jump = true })
  end
end)
km.nnoremap('<C-k>', function()
  if not trouble.is_open() then
    trouble.open()
  else
    trouble.previous({ skip_groups = true, jump = true })
  end
end)

[jrnxf]

@folke I saw you add expose the is_open method earlier - ty for that! Could I get your thoughts on this PR when you get the chance?

[folke]

Looking good!

You can remove the loop config option and just make it the default. Thanks!

[jrnxf]

Updated! I also exposed the is_open directly on the Trouble module like the rest of the methods, since it seemed odd to have it be the only one that was exposed differently

[folke]

Awesome, thanks!

[tom-anders]

Is there an easy way to turn off this new behavior? For me it's pretty annoying and unexpected