Outdated Petrol & Diesel V8 engines for the ETK 800/K series 4.2.1

Hello all, I finally found some time to work on this mod so I added a bunch of new content and fixed some problems :

- Added a new stage 2 twin turbocharger that makes a bit less than 800HP and 1100NM
- Added a new "Ultra High Performance Radiator" to cool down this bad boy
- Slightly reduced the strength of the stock long block to make it break when there's the stage 1 (or above) turbocharger selected
- Greatly decreased the strength of the high rpm long block to make it break very quickly when a forced induction is selected
- Reduced the power of the Drag long block but raised the power of the stage 3 turbocharger (the Drag config
- Slightly raised the power of the stock twin tubocharger version (~ +20HP)
- Tweaked the exhaust sound balance that had not enough muffling
- Fixed some typos in the config's descriptions