Adding optional files to contain JSON objects for clientContext and i…

[Skorch]

Adding optional files to contain JSON objects for clientContext and identity to be passed into the lambda_invoke command.

[Skorch]

The identity.json file is formatted as such:

{
  "cognitoIdentityId": "us-east-1:f9ce8f14-81c3-4c63-81b3-xxxxxxxxxxxx",
  "cognitoIdentityPoolId": "us-east-1:a541b935-bfea-4be6-b842-xxxxxxxxxxx"
}

The client_context.json is formatted as such:

{
  "client":{
    "installation_id" : "id_123",
    "app_version_code": "1.0",
    "app_version_name": "app version name",
    "app_package_name": "app package name",
    "app_title": "app title"
  },
  "env": {
    "platform_versioin": "9.1",
    "platform": "ios",
    "make": "iPhone",
    "model": "6",
    "locale": "ca"
  }
}