~/.muttrc: Add shortcuts for mailboxes (1, 2, 3)

.muttrc

macro index E "<enter-command>set editor=\"~/k/editlabel menu\"\n<edit><sync-mailbox><next-undeleted><enter-command>set editor=vim\n" "Edit labels"
# bindings
## edit/move many messages
macro index = <tag-prefix>
macro index * <tag-entry>
bind index n next-unread-mailbox
## changing mailboxes
macro index 1 "<change-folder>=lu/INBOX<enter>"
macro index 2 "<change-folder>=htwk.imn/INBOX<enter>"
macro index 3 "<change-folder>=htwk/INBOX<enter>"
bind  index n next-unread-mailbox
# colors
source $HOME/t/mutt-colors-solarized/mutt-colors-solarized-dark-16.muttrc