Save user's e-mail when she publish an app

[jfresco]

Tasks

• [x] Make the Contact field required.
• Create an email field in the users collection and:
  • [x] at signup, extract the e-mail from the GitHub API payload and save it in the email field;
  • [x] run a data migration which parses the existing raw data, extract the e-mail and put it in the email field.

[jfresco]

Currently, we are collecting e-mail information from two sources:

1. Applications. When somebody uploads an app, there is a Contact field, which is optional. Currently 50 of 87 apps don't have a value in this field.
2. Log in information. When a user signs up using GitHub, the API returns lot of user information including the e-mail. The data is in a JSON string, meaning that we need to parse it in order to extract the e-mail. Twitter API doesn't provide this data.

Considering this scenario, I propose two tasks to do here:

1. Make the Contact field required.
2. Create an email field in the users collection and:
   1. at signup, extract the e-mail from the GitHub API payload and save it in the email field;
   2. run a data migration which parses the existing raw data, extract the e-mail and put it in the email field.

Thoughts? @mjlescano @gvilarino @Annagramma

[mjlescano]

LGTM