* swarm/network/stream: remove old syncing test and replace it with two more granular tests, with the first one testing a full sync between two nodes (makes sure that when all subscriptions are established on all bins - all content is replicated from one node to the other), and a second test that adds a bigger amount of nodes to a star network topology, effectively making the pivot node have a depth > 0 to sync just certain content to the connected nodes (due to a star topology this test (always 1 hop) does not check that, for example, specific content is routed across multiple nodes, but assumes content should be only on the most proximate node)
* api, cmd/swarm-smoke, fuse, network, storage: fix data dir leak when using ephemeral filestore, pull test params to be easily adjustable
