Add Enums to improve readability

[brandonmanke]

Enums based off of some of the enums or objects in the API would help make parameters easier to understand and improve readability. For example membershipType constructing a simple enum based off of the API Enum type.

const destinyMembershipType = {
  None: 0,
  TigerXbox: 1,
  TigerPsn: 2,
  TigerBlizzard: 4,
  TigerDemon: 10,
  BungieNext: 254,
  All: -1
};

Will probably include them in their own seperate file, named destiny-types or something.