Integrate dsync + fixes

[Wulf]

I've had this stashed for a while, finally ended up testing it tonight and it looks like it's ready to go. I'll list the changes this brings shortly.

• Can't run cargo fullstack using poem server #64 fixes dependency issues

• CASCADE ALL in postgresql down.sql files. #57 migration files

• cargo fullstack issues on Windows #53 (related PR: Call yarn as "yarn.cmd" on Windows (fixes #53) #65): switched to using tsync as a library which should partly fix the errors we're seeing here on windows

• Remove plugin-auth dependency for plugin-dev #52 wasn't entirely fixed, but I've added a test to make sure projects aren't generated which have the dev but not the auth plugin enabled

• Integrated dsync

• Fixed the starter template a bit