Add copyright

README.md

@@ -4,4 +4,6 @@ CutefishOS's system wallpaper.
 
 ## License
 
+* [Unsplash License](https://unsplash.com/license)
+
 This project has been licensed by GPLv3.

sources/copyright

@@ -0,0 +1,23 @@
+Fakurian Design
+https://unsplash.com/photos/bexwsdM5BCw
+https://unsplash.com/photos/jkqGsgsE0RY
+https://unsplash.com/photos/F93PQmh4krI
+https://unsplash.com/photos/atA59lx_WkM
+
+Sebastian Svenson
+https://unsplash.com/photos/LpbyDENbQQg
+
+Katarina Šikuljak
+https://unsplash.com/photos/aY-Ic8Cw1Jw
+
+Petar Petkovski
+https://unsplash.com/photos/Wh2FhL0v_eo
+
+Luke Chesser
+https://unsplash.com/photos/zFaSM1hz02c
+
+Albert Bleeker
+https://unsplash.com/photos/slpTDuenYeM
+
+Chevanon Photography
+https://www.pexels.com/photo/close-up-of-a-red-siamese-fighting-fish-325044/