How to Return Riak Objects Sorted by Key Value?
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I have a bucket called 'employees'.  In it are keys that look like this:

    "ryan_07-01-2012_8:15pm"
    "joy_07-02-2012_8:20pm"
    "ryan_07-03-2012_8:30pm"
    "tammy_07-05-2012_8:10pm"
    "tammy_07-11-2012_8:01pm"
    "joy_07-15-2012_8:20pm"

All of the keys point to Riak objects that look similar to this:

    { description: "left the office", signed-out: "8:15pm" }

In Riak, especially with php client, riak-php, how would you return the objects ordered by time and date based on the key values ( ie "ryan_07-01-2012_8:15pm" ).  