Added jsr166 backport reference, fixed cast bugs

Author: akarnokd

flow-bridge/build.gradle

@@ -1,4 +1,11 @@
 description = "reactive-streams-flow-bridge"
+
+repositories {
+    maven { url 'http://repo.spring.io/libs-snapshot' }
+    maven { url "https://oss.sonatype.org/content/repositories/releases/" }
+}
+
 dependencies {
     compile project(':reactive-streams')
+    compile "io.projectreactor:jsr166:1.0.0.BUILD-SNAPSHOT"
 }

flow-bridge/src/main/java/org/reactivestreams/ReactiveFlowBridge.java

@@ -43,7 +43,7 @@ public static <T> Flow.Publisher<T> toFlow(
             org.reactivestreams.Publisher<? extends T> reactivePublisher
     ) {
         Objects.requireNonNull(reactivePublisher, "reactivePublisher");
-        if (reactivePublisher instanceof org.reactivestreams.Publisher) {
+        if (reactivePublisher instanceof Flow.Publisher) {
             return (Flow.Publisher<T>)reactivePublisher;
         }
         if (reactivePublisher instanceof ReactivePublisherFromFlow) {
@@ -85,7 +85,7 @@ public static <T, U> Flow.Processor<T, U> toFlow(
             org.reactivestreams.Processor<? super T, ? extends U> reactiveProcessor
         ) {
         Objects.requireNonNull(reactiveProcessor, "reactiveProcessor");
-        if (reactiveProcessor instanceof org.reactivestreams.Processor) {
+        if (reactiveProcessor instanceof Flow.Processor) {
             return (Flow.Processor<T, U>)reactiveProcessor;
         }
         if (reactiveProcessor instanceof ReactiveToFlowProcessor) {