Update Mutt config

- check for new mail either every 15 minutes or when prompted
- simplify the index (list of messages)
Update vim config

- ignore .swp files
- open the current directory when splitting windows and opening tabs
- add more emacs keybindings
Favor xdg-open over open

There's some lag time between a command not being found when running
this || command from Mutt and the next command running.