[split] Move local-config plugin to oh-my-fish/plugin-local-config

https://github.com/oh-my-fish/plugin-local-config

plugins/local-config/local-config.load

-# Load custom settings for current hostname
-set -l HOST (hostname | sed -E 's/(-[0-9]+)?(\.(local|home))?$//')
-set -l HOST_SPECIFIC_FILE $fish_custom/hosts/$HOST.fish
-if test -f $HOST_SPECIFIC_FILE
-  . $HOST_SPECIFIC_FILE
-else
-  echo Creating host specific file: $HOST_SPECIFIC_FILE
-  mkdir -p (dirname $HOST_SPECIFIC_FILE)
-  touch $HOST_SPECIFIC_FILE
-end
-
-# Load custom settings for current user
-set -l USER_SPECIFIC_FILE $fish_custom/users/(whoami).fish
-if test -f $USER_SPECIFIC_FILE
-  . $USER_SPECIFIC_FILE
-else
-  echo Creating user specific file: $USER_SPECIFIC_FILE
-  mkdir -p (dirname $USER_SPECIFIC_FILE)
-  touch $USER_SPECIFIC_FILE
-end
-
-# Load custom settings for current OS
-set -l PLATFORM_SPECIFIC_FILE $fish_custom/platforms/(uname -s).fish
-if test -f $PLATFORM_SPECIFIC_FILE
-  . $PLATFORM_SPECIFIC_FILE
-else
-  echo Creating platform specific file: $PLATFORM_SPECIFIC_FILE
-  mkdir -p (dirname $PLATFORM_SPECIFIC_FILE)
-  touch $PLATFORM_SPECIFIC_FILE
-end