CLC-3852 Smoke test shouldn't burn down the server

https://jira.ets.berkeley.edu/jira/browse/CLC-3852

The first commit stops our ongoing ping-all-APIs-by-default madness.

The second commit keeps simple mistakes from triggering a full Hot Plate run.
Apologies for missing this note, @christianv ! Yes, ".to_i" is one of the nastier design-bugs in Ruby, because non-numeric strings get silently turned into zero. As a result, you don't know whether the actual input was "0" or was something like "ERROR: Could not reach remote server!" It's almost always better to do the Integer(string, 10) & exception-catch instead. It's verbose & ugly, but it's the standard recommended practice.