Feature: inbuilt benchmarks

[omeh-a]

Currently, ipbench only has the inbuilt capability to run single tests. This is not terribly useful. At TS we get around this with big scripts which run the tests and assemble the data.

To foreign users, this is one of the big hurdles that prevents ipbench from being useful straight out of the gate. Competing ip benchmarking programs are all capable of running complete benchmarks "right out of the box". Even for us here, there are different scripts used by different members and this creates lots of needless complexity and frustration.

Goal: premade benchmarks either as:
a. A set up easy to use, understand and extend scripts
b. A core feature of ipbench -> e.g. ipbench --bench latency-throughput

[omeh-a]

It would make a lot more sense to bundle this functionality into a separate program called something like ipbench-test - this way the philosophy of the core ipbench system remains unchanged. This would be useful for debugging too - especially if #11 was combined into this functionality. E.g. to run a sanity check on new features, ipbench-test --localtest might locally spin up a tester daemon + controller and target a local echo server silently.