Add Papers icon

[Raindrac]

Adds an icon for the official Gnome replacement for Document Viewer, aka Evince. It's now a core Gnome app.

Design Decisions

The shade of red used is from the Gnome Photos icon in Papirus. The remaining colors are frequently used in Papirus for paper and/or provided in the example color palette.

Because the paper at the bottom of the stack uses a gradient from blue to purple in the original icon, I decided to create an illusion of a gradient by using blue on the top half of the paper and purple on the lower half. Because the transition is hidden by the papers above it, it looks seamless and preserves the solid color design guideline of Papirus.

Much like the Papirus icon for Evince, I didn't include the glasses. It makes for a cleaner look and puts the focus on the documents that Papers is intended to view.

[morganist]

please don't forget to run prepare.sh when getting icons ready for pull request! it gets rid of the unnecessary tags in the svg file. (like inkscape window size!)

[Raindrac]

Oh, I didn't forget it. I ran prepare.sh, but I had to undo it because it caused some objects to change their position. Is there something that can be done about that?

[Raindrac]

There we go, this should be ready to merge now. I managed to get it fixed, removing the transforms and unnecessary tags, and once I did prepare.sh worked just fine 🙂