Prompt for registration on install until successful.

Closes #2657

// FREEBIE

src/org/thoughtcrime/securesms/RegistrationActivity.java

@@ -160,8 +160,6 @@ public class RegistrationActivity extends BaseActionBarActivity {
     public void onClick(View v) {
       final RegistrationActivity self = RegistrationActivity.this;
 
-      TextSecurePreferences.setPromptedPushRegistration(self, true);
-
       if (TextUtils.isEmpty(countryCode.getText())) {
         Toast.makeText(self,
                        getString(R.string.RegistrationActivity_you_must_specify_your_country_code),

src/org/thoughtcrime/securesms/service/RegistrationService.java

@@ -292,6 +292,7 @@ public class RegistrationService extends Service {
     TextSecurePreferences.setPushServerPassword(this, password);
     TextSecurePreferences.setSignalingKey(this, signalingKey);
     TextSecurePreferences.setSignedPreKeyRegistered(this, true);
+    TextSecurePreferences.setPromptedPushRegistration(this, true);
   }
 
   private void setState(RegistrationState state) {