Added .setbanner command

src/NadekoBot/data/strings/commands/commands.en-US.yml

@@ -402,6 +402,10 @@ setavatar:
   desc: "Sets a new avatar image for the NadekoBot. Parameter is a direct link to an image."
   args:
     - "https://i.imgur.com/xTG3a1I.jpg"
+setbanner:
+  desc: "Sets a new banner image for the NadekoBot. Parameter is a direct link to an image. Supports gifs."
+  args:
+    - "https://i.imgur.com/xTG3a1I.jpg"
 setgame:
   desc: "Sets the bots game status to either Playing, Listening, or Watching."
   args:

src/NadekoBot/data/strings/responses/responses.en-US.json

@@ -184,6 +184,7 @@
   "setrole": "Successfully added role {0} to user {1}",
   "setrole_err": "Failed to add role. I have insufficient permissions.",
   "set_avatar": "New avatar set!",
+  "set_banner": "New banner set!",
   "set_channel_name": "New channel name set.",
   "set_game": "New game set!",
   "set_stream": "New stream set!",