Wrap calls to setgenerate...

...and drop unnecessary rpc call to getblockcount, since every simulation
starts over.
Fix tps estimation in controlled simulations
close stop chan first so Shutdown can proceed
IMPORT PATH MODIFICATION CHANGESET
----------------------------------

Please use this changeset as the first one on top of the conformal codebase.
Note that if there are new imports, they need to be changed as part of this
changeset. In general, use "git rebase" on github.com/conformal's version
and apply this changeset first.