Add file-upload plugins for participants' import[Fixes #46983567]
Add participants' mass-import functionality (unfinished)[Fixes #46983567]
Refactor group_name into pool_name in tournament.js and tournament.sql [Fixes #46983567]
Test bootstrap popover [Fixes #46983567]
Merge remote-tracking branch 'origin/master'

Conflicts:
	assets/js/tournament.js
	views/tournaments_add_view.php