Add a trifle of i18n to KeyVerificationView

Two strings were left behind:
- "Their identity (they read)"
- "Your identity (you read)"

I saved them.

// FREEBIE

js/views/key_verification_view.js

@@ -27,6 +27,8 @@
         render_attributes: function() {
             return {
                 verifyIdentity: i18n('verifyIdentity'),
+                yourIdentity: i18n('yourIdentity'),
+                theirIdentity: i18n('theirIdentity'),
                 your_key: this.splitKey(this.model.your_key),
                 their_key: this.splitKey(this.model.their_key)
             };