Merge pull request google#790 from google/jwilson_0211_java_16

Build Gson for Java 1.6.

Author: swankjesse

pom.xml

@@ -24,7 +24,7 @@
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <java.version>1.7</java.version>
+    <java.version>1.6</java.version>
   </properties>
 
   <scm>