Added prompt_login for old fish shell and customisation of prompt_login

fish_cfg/functions/prompt_login.fish

@@ -0,0 +1,19 @@
+function prompt_login --description 'display user name for the prompt'
+    # If we're running as root, change the user color and the seperator
+    if functions -q fish_is_root_user; and fish_is_root_user
+        if set -q fish_color_cwd_root
+            set fish_color_user $fish_color_cwd_root
+        end
+ 		set seperator '☠'
+	else
+		set seperator '@'
+	end
+
+    # If we're running via SSH, change the host color.
+    set -l color_host $fish_color_host
+    if set -q SSH_TTY; and set -q fish_color_host_remote
+        set color_host $fish_color_host_remote
+    end
+
+    echo -n -s (set_color $fish_color_user) "$USER" (set_color normal) $seperator (set_color $color_host) (prompt_hostname) (set_color normal)
+end