Add a "manage.status" runner that gives a combined up/down report

It would be nice to get the up/down state of all salt minions in a single command.  The current runners make it so that two commands are needed to get this information

This adds a new "manage.status" runner that will print a report of the up/down state in a consumable format (YAML).  It also refactors the up() and down() runners to use a common code path

Example output:

    # salt-run manage.status
    down:
    - minion1
    up:
    - master
    - minion2
    - minion3