Move long-running benchmarks to src/bin/

[garious]

The long-running benchmarks don't need libtest or criterion and could make use of debug symbols for debugging. Neither the integration tests or the benchmarks is the right place for them. Until we can think of a more appropriate place, let's move them to src/bin/bench-*.

• Rename src/bin/client-demo.rs to src/bin/bench-tps.rs and output binary to solana-bench-tps.
• Move benches/streamer.rs to src/bin/bench-streamer.rs, purge criterion, and output binary to solana-bench-streamer.