Feature: Update roll, add check, add combination

[Nmarinsiruela]

Hello! So I've decided to take a hit at this awesome bot!

Being a Chronicler player, I had to make some updates, I hope this is not complex to make!

The main points of this PR are:

• Set up a utility function to make the rolls ---> check now takes care of this!
• Add a 'check' command ---> Useful to really make sure that you know what are you rolling!
• Add a 'combi' command ---> Let's add logic for combination rolls!
• Add the automatic trigger option ---> You can automatically add triggers. Useful if you have a potential that enables you this!

[MrMstislav]

PR rejected: this is not pep 8 compliant

(joking, gracias por el currazo!)