list safe image websites in ublog form

app/views/ublog/form.scala

@@ -81,6 +81,23 @@ object form {
           if (ctx isUserId post.created.by)
             frag(
               p(trans.ublog.uploadAnImageForYourPost()),
+              p(
+                "It is safe to use images from the following websites: ",
+                fragList(
+                  List(
+                    "unsplash.com"        -> "https://unsplash.com",
+                    "creativecommons.org" -> "https://searchcreativecommons.org",
+                    "pexels.com"          -> "https://pexels.com",
+                    "piqsels.com"         -> "https://piqsels.com",
+                    "freeimages.com"      -> "https://freeimages.com"
+                  ).map { case (name, url) =>
+                    a(href := url, targetBlank)(name)
+                  }
+                )
+              ),
+              p(
+                "You can also use images that you made yourself, pictures you took, screenshots of Lichess... anything that is not copyrighted by someone else."
+              ),
               p(trans.streamer.maxSize(s"${lila.memo.PicfitApi.uploadMaxMb}MB.")),
               form3.file.image("image")
             )