As a jungle how do i pick/play against a tank comp?

Thanks to the buffs made in both crowd control as well as health/tank items being easier to build. There have been a lot of people building tank comps like "Cho'gath mid, Sion jungle, Maokia top , leona support, with a long range adc or high poke like corki or jinx". i have had a very hard time time playing against comps like this. My main champions at the moment have been Volibear, Rek'Sai, Nautilus and Master Yi.

1. What champions are best against these comps?
2. How should I play against them as well?

Currently I build according to what the enemy's biggest threat is and/or on how far ahead I am compared to that threat. Quick example is on Rek'Sai I rush hydra if they have a fed ap laner then slowly build visage but I change that to something more economical if i am behind.

3. If I should change how I itemize how should i change it

One last thing I didn't add early on which had been happening a lot also due to the tank meta that is upon us. I'm not going to add anymore to this but it is something that I think needs some attention as well.

Another not so completely jungle but game related is this. I've had a lot of games where again dealing with a tank comp and there is a team fight. For some very very odd reason my team does not focus the tank or front line they always try to get to the back line even though their champs are not tanky and are completely shut down by the enemy team's cc. quick example here would be a kata diving a carry with a leona or cho'gath maokia protecting him.

4. Lastly how do you team fight against these compositions, and how should you also get your team to fight them or help you when using the strategy you use in these situations?