Run create host more, setup host less

In this commit https://github.com/evergreen-ci/evergreen/commit/e4da95da76f03a2611e0226e966ec29b738e9ca4 we throttled hostinit on the theory that it is the cause of us hitting AWS API limits. However, from Splunk graphs from a period where we started 300 new hosts in 10 minutes, it's clear that the biggest user of the API is setup host. Since we pay up front for a minute, and since it may take that long for hosts to spawn, we should run setup host at the same rate that we run create host.

See link to graph in comment.