Description of the issue
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If a meeting fails to create on the Adobe Connect server, it won't let you recreate it with the same name. It says that a meeting with the same name already exists, when in fact it is just an orphan record on Moodle's side.

Steps to reproduce
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Try and create a meeting with foreign characters (such as Malmö). It will appear to have worked, but when you click on the meeting name on the course page it tells you that no meeting could be found on the server. If you try to recreate a meeting with the same name, it won't let you.

Expected Behaviour
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If a meeting fails to create, it should tell you. It should gracefully roll back (deleting any references to that activity's meeting(s) in Moodle's database so that there are no orphaned entries)

Resolution
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If aconnect_create_meeting() fails (returns false) it should remove any references to the activity's meeting(s) on Moodle, and delete any meetings from the server (If, for example, the activity is created in group mode, the site has 5 groups, and one of the group names has a character that causes it to fail. Moodle could create some of the activities before failing, so it's important to delete that subset)

Patch and github repo
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Links to be provided in comments section once I get a tracker number for this issue