Add TPC-C 10 + other workload improvements

[nstewart]

This update adds TPC-C 10 and ensures the workload generators have an affinity for running on nodes that do not contain CockroachDB servers.

This gives us a pattern for adding arbitrary workloads to the cockroachdb cloudformation template

cc @robert-s-lee @rkruze @danhhz

Closes #26

[nstewart]

I'm still running tests but creating a PR to get feedback on the approach.

[nstewart]

OK, updated tests and confirmed TPC-C 10 works

The workload is tagged with the appropriate app for the statements page

[danhhz]

When I added workload to the cockroach binary, I felt like I didn't have enough data on whether to include ycsb and kv, so defaulted to leaving them out. Do either of you have an opinion here?

[nstewart]

@danhhz I'd like all of our supported workloads to be a part of the workload command! My big question is how to make it easier to load large fixtures (potentially without an enterprise license)

[danhhz]

I'd like all of our supported workloads to be a part of the workload command!

Happy to do this if there's a canonical list of them somewhere.

My big question is how to make it easier to load large fixtures (potentially without an enterprise license).

With an enterprise license, this is currently possible but requires a google cloud account that we can tell google to charge for the transfer bandwidth. It's also doable to make it work without the enterprise license but there are some tradeoffs that I don't have the data to make (some of which even get around the google account requirement). Also happy to do this (tho not for 2.1.0) if you want to be my design partner.