Make final

Author: benjchristensen

rxjava-core/src/main/java/rx/schedulers/Schedulers.java

@@ -23,7 +23,7 @@
 /**
  * Static factory methods for creating Schedulers.
  */
-public class Schedulers {
+public final class Schedulers {
 
     private final Scheduler computationScheduler;
     private final Scheduler ioScheduler;