Use ~/.gvimrc.min or ~/.vimrc.min if one exists

## Use ~/.gvimrc.min or ~/.vimrc.min if one exists
This option is useful if you want to use a minimal version of .vimrc and improve startup time
For example, my `.vimrc.min` only consists of built-in features (no plugins)
https://github.com/daeyun/dotfiles/blob/master/.vimrc.min

## Clean up $TMPFILE_DIR
1. Delete files older than 60 minutes
2. Overwrite once before deleting as a basic security measure