Verify Thread Count is numeric before launching the AWS instances

[babakontheweb]

Assume you've been running your jMeter tests locally to validate before running jmeter-ec2, you may have set up your Thread Count as a parameterized value. If you run jmeter-ec2 now, you will launch the instances and copy the files over only to get this error message.

The validation of the .jmx file can be performed locally before launching any instances. The benefits here are

1. The error is identified immediately, without having to wait for all the instances to launch only, copy, and validate.
2. You don't incur the hourly cost of the instances (as low as they may already be).

[oliverlloyd]

I can imagine that was annoying when you got that message, sorry about that, but thanks for the issue.