* p2p/simulation: WIP minimal snapshot test
* p2p/simulation: Add snapshot create, load and verify to snapshot test
* build: add test tag for tests
* p2p/simulations, build: Revert travis change, build test sym always
* p2p/simulations: Add comments, timeout check on additional events
* p2p/simulation: Add benchmark template for minimal peer protocol init
* p2p/simulations: Remove unused code
* p2p/simulation: Correct timer reset
* p2p/simulations: Put snapshot check events in buffer and call blocking
* p2p/simulations: TestSnapshot fail if Load function returns early
* p2p/simulations: TestSnapshot wait for all connections before returning
* p2p/simulation: Revert to before wait for snap load (5e75594)
* p2p/simulations: add "conns after load" subtest to TestSnapshot
and nudge