Permissions arrays can have duplicates

[lyntco]

Getting stuff like this:

 permissions:
   [ { entity: 'dd36730e-f449-4e24-9854-90905c7757f9',
       type: 'purchaser' },
     { entity: '31ba0784-2e6b-4679-86c1-320802d02fa2',
       type: 'purchase' },
     { entity: '31ba0784-2e6b-4679-86c1-320802d02fa2',
       type: 'purchase' },
     { entity: '31ba0784-2e6b-4679-86c1-320802d02fa2',
       type: 'purchase' },
     { entity: '31ba0784-2e6b-4679-86c1-320802d02fa2',
       type: 'purchase' } ],
  rev: 'fac9c07e-6ee7-4e34-8d3e-4357e24532df',
  updated_at: '2015-12-24T06:13:51.658Z' }

Should be a way to compact the dups.