TeamLevels:

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   Assign a hierarchical level to each team in the array. 

   Since version 7.
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   Form:
   [levels,teams] = TeamLevels(teams)
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   Inputs
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   teams           (.)  Data structure array of N teams, with the following fields:
                          - name:           name of team (string)
                          - memID:          member ID numbers (1-D numeric array)
                          - refID:          reference ID number 


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   Outputs
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   levels         (1,N)   Level of each team. (Level 1 is at top of hierarchy).
   team            (.)    Original team data structure array, with levels updated

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