Show the button log in.

app/src/main/res/layout/fragment_authentication_log_in.xml

@@ -43,8 +43,11 @@
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_marginBottom="16dp"
+        android:layout_marginEnd="@dimen/screen_edge_left_and_right_margins"
+        android:layout_marginStart="@dimen/screen_edge_left_and_right_margins"
+        android:gravity="center"
         android:text="@string/msg_new_in_rocket_chat"
-        app:layout_constraintBottom_toBottomOf="parent"
+        app:layout_constraintBottom_toTopOf="@+id/button_log_in"
         app:layout_constraintLeft_toLeftOf="parent"
         app:layout_constraintRight_toRightOf="parent" />
 
@@ -52,7 +55,6 @@
         android:id="@+id/button_log_in"
         style="@style/AuthenticationButton"
         android:text="@string/title_log_in"
-        android:visibility="gone"
         app:layout_constraintBottom_toBottomOf="parent" />
 
 </android.support.constraint.ConstraintLayout>
\ No newline at end of file