[xmonad] darcs patch: Shell.hs: getEditor/Browser changes

Thu Apr 3 18:38:12 EDT 2008 gwern0@gmail.com * Shell.hs: getEditor/Browser changes This implements the discussed changes. getEditor now defaults to testing $VISUAL, then $EDITOR. getBrowser tests additional variables, $X-WWW-BROWSER/$WWW-BROWSER. The fallback for getEditor is now emacsclient. Advice is added for Vim users to use gvim by default. The env function is generalized to getEnv on a list; particular thanks to allbery_b who basically wrote the new one - I certainly wouldn't've figured out that use of MonadPlus!