A slight change to rewards (Patreon)

I've just made an adjustments to how the rewards work for this patreon. I've reworded the reward discription to make it clearer that you only get the 5$ and 10$ rewards for comics that you paid for. And I've added a new reward 15$ tier that gives you access to all past rewards. Right now it isn't really worth it, but at some point it will be haha. 

This changes nothing for people who already paid for "Spicing Things Up" part 1. It only really matters for people who pledged after I made the paid post for that comic.

I am sorry if I made things confusing! Originally I wanted to just do what I do for my other patreon. Have everybody who pledged 5$ get access to every single past 5$ reward, but after some thinking I figured it isn't fair to people who pledged for multiple comics. 

Let me know what you think!