Decouple project home from jmeter-ec2 code

This makes it easier to have one instance of jmeter-ec2 on your machine, but store multiple test setups in different places.

Auto detect `$LOCAL_HOME` and `$project` and use `$project_home` in place of `$LOCAL_HOME/$project`.

Remove unneeded executable permission on `*.properties` files (since they are sourced with `.`, they don't need to be executable).

Finally, a bunch of really small whitespace cleanups (my linter automatically does the clean up).