First pass at revising command handler
'handled' code is now decoupled from error code
Convert more command handlers. Implement help <command>.
update all
update kasp
update keyzones
policy list
policy import
policy export
policy purge, zone list
zone del, zone add
zonelist import/export
ds gone/retract/seen/submit
more converted
rest of commands
Zone list not handled due copy/paste error
cought another copy err
Command needs to be consumed.
A hack te prevent command handler print "zonelist export
completed in 0 seconds.". To properly fix it the client should
distinguish between stdout and stderr (TODO)
include copyright
Merge pull request #35 from yschaeff/command_handler

Revising command handler