Adds notification when there’s a new release available

[kennethormandy]

Let people know when there’s a new release of Surge available using update-notifier. The default timing settings are left in place, so you’d only see a notification at most once each day you use Surge, and never until after you’d completed a deploy.

[kennethormandy]

To follow up our previous discussion, the info on when to ask to update again is stored in ~/.config/configstore/update-notifier-surge.yml, along with any other global config for Insight, Update Notifier, and Yo.

The file itself will look something like:

optOut: false
lastUpdateCheck: 1431021283294

[fearphage]

Reverse this if for clarity's sake. When the situation is special, do something special.

if (special && case) {
  takeSpecialAction();
}
// always take this action
next();