vimrc: add settings for rust and shell files
vimrc: ignorecase
xmobarrc: show day of week
xmonad: remove automatic workspace assignments
xmonad: rename workspaces
xmonad: add mapping to switch to workspace 0
xmonad: add mapping to lock screen
xsession: update startup applications
mutt: add zenburn color theme
muttrc.outlook: add mutt config for outlook
muttrc: update for herebedragons
muttrc.zenburn: rename