Simulate more advanced use cases

[Arqu]

• Try 50 node transfers and various mesh setups
• Simulate tests: big sync test (wip) iroh#1514

minimal repro could be this:
P1 creates a doc + ticket
P2, P3, P4 join
P4 goes offline
P4 adds entries while offline
P4 goes online again (rejoins P1)
check after some timeout that P3 and P2 have the new entries from P4. I would guess that only one of them will have them. If it works, try the same with more peers, then it will fail.

• Diva outlined some good use cases