Add support for servers to deliver response headers
Fixes some propagation issues for trailers too
Adds some more testing for metadata exchange

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77979593
diff --git a/core/src/main/java/com/google/net/stubby/Metadata.java b/core/src/main/java/com/google/net/stubby/Metadata.java
index 602b218..37fbc64 100644
--- a/core/src/main/java/com/google/net/stubby/Metadata.java
+++ b/core/src/main/java/com/google/net/stubby/Metadata.java
@@ -449,7 +449,7 @@
      */
     private Key(String name, Marshaller<T> marshaller) {
       this.name = Preconditions.checkNotNull(name, "name").toLowerCase().intern();
-      this.asciiName = name.getBytes(US_ASCII);
+      this.asciiName = this.name.getBytes(US_ASCII);
       this.marshaller = Preconditions.checkNotNull(marshaller);
     }