introduce Translate API

[stephenplusplus]

Fixes #977

To Dos

• Enable Translate API for Travis account
• Set env var in Travis for API key
• Docs
• Tests
  • Unit
  • System

Preview

var gcloud = require('gcloud');

var translate = gcloud.translate({
  key: 'API Key'
});

// Translate a string of text.
translate.translate('Hello', 'es', function(err, translation) {
  if (!err) {
    // translation = 'Hola'
  }
});

// Detect a language from a string of text.
translate.detect('Hello', function(err, results) {
  if (!err) {
    // results = {
    //   language: 'en',
    //   confidence: 1,
    //   input: 'Hello'
    // }
  }
});

// Get a list of supported languages.
translate.getLanguages(function(err, languages) {
  if (!err) {
    // languages = [
    //   'af',
    //   'ar',
    //   'az',
    //   ...
    // ]
  }
});

[stephenplusplus]

@callmehiphop PTAQL. This one's pretty small. I just want to be sure I'm not doing anything too crazy before locking it up with the unit tests.

[callmehiphop]

@stephenplusplus LGTM :) unit test away!

[stephenplusplus]

Thanks for the review!

[jgeewax]

/cc @ilsung

Does Translate work with service account credentials (ie, keyfile.json) ?

[stephenplusplus]

Tests added: stephenplusplus@1ebcde0

[stephenplusplus]

Marking as blocked until we hear from @ilsung about authenticating with a service account keyfile. (Thanks in advance for your help!)

[ilsung]

Sorry for the delay -- No, the Translate API does not support service account creds since it doesn't use OAuth. A key is required.

[stephenplusplus]

Thanks for clearing that up.

@callmehiphop if this LGTY, merge away.

[callmehiphop]

🍰