Single param without equal sign or value shouldn't cause an empty result

[Eli Doran]

See code here.

var sqs = require('simple-query-string')
  , query = '?key'
  , result = sqs.parse(query)

console.log(result)

// outputs: {}

// should output: { key: null }

[Khalid Salomão]

Fixed in release 1.3.1!
Thanks!