More paranoid default permissions (umask 077) [zsh]

i.e. zero permissions to other users.
Reorganize some vi mode zle widgets [zsh]

Nothing fancy, just add b/B to ciw/diw/etc. and convert to explicit
function() declarations.
Set KEYTIMEOUT to 200ms [zsh]

This fixes diw/ciw/etc. not working in zsh CMD mode (vi mode).