Delete unused variable in simulation test
Remove interpolation for Flakiness in report since value is never given.

Also remove unnecessary whitespace and blank comments
Add new stats to simulation reports

- Add stats for memory and disk usage on reps
- Add stats for how much multi-instance app colocation exceeds ideal amount of colocation
- Add descriptive title for each simulation report
- Reorganize simulation report
- Refactor reports to use GoStats library for computations