Several zsh option changes, including noextendedglob:

- extendedglob breaks typing of literal ^ and # as unquoted strings
- dvorak to make spelling correction better (untested)
- set automenu to get menu completion after second Tab
- set bareglobqual to get the benefit of *(.) *(/) *(@) etc.

Also add comments explaining why some of the options are enabled,
along with TODOs for investigating some others that were previously
enabled.