Add-ons don't play well with synchronized breaks

[ctm]

FIgure out how to make add-ons play with synchronized breaks.

I added add-ons before adding synchronized breaks. When I added synchronized breaks I didn't think about add-ons and the fact that they're level based and normally are set up to occur on breaks.

I'm labeling this high priority but only so that I can think about it and figure out how to proceed. Unless it's super easy to fix, I'll probably strip high priority from the implementation.

[ctm]

I never really did think about this much, but my inclination is to make it so that a one minute break is added for people to decide whether or not to add on. However, what if that break is super close to the synchornized break? Should the synchronized break be used instead?

Since there are no structures with add-ons in WSOPS, this is definitely not a high priority. However, it's still a bug, so once I'm done with high priority items, it probably makes sense, at minimum, to disallow synchronized breaks when add-ons are present and probably to also not offer structures that can't have synchronized breaks in the default list of structures people can pick.