Add support for twitter account files

[mrbrianevans]

Add a post processor, typescript interface and random generator of twitter account.js files.

Sample:

{
  "account" : {
    "email" : "string",
    "createdVia" : "oauth:number",
    "username" : "string",
    "accountId" : "number",
    "createdAt" : "date",
    "accountDisplayName" : "string"
  }
}