[split] Move localhost plugin to oh-my-fish/plugin-localhost

https://github.com/oh-my-fish/plugin-localhost

plugins/localhost/localhost.load

-# Opens http://localhost:3000 (and other ports) in the default browser
-#
-# Usage:
-#
-# open a commonly used port with just the port number
-# $ 3000
-#
-# open an arbitrary port using the `lh` command
-# $ lh 3001
-
-## Functions
-function _open-installed
-  which open >/dev/null ^&1
-end
-
-## Main program
-function lh
-  if _open-installed
-    if [ (count $argv) -lt 1 ]
-        echo "You need to specify a port to open"
-        return 1
-    end
-    command open http://localhost:$argv
-  else
-    echo 'Requires open (MacOS only) to be installed'
-  end
-end
-
-set -l common_localhost_ports 3000 4000 5000 6000 7000 8000 8001 9000 8080
-
-for port in $common_localhost_ports
-  eval "function $port; lh $port; end"
-end