Bump Java to 1.7

Change-Id: I7c9ad6d4c4f7d711b6e5c1653fe36560098c1e3a

pom.xml

diff --git a/pom.xml b/pom.xml
index 1951d74..96233d2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -241,8 +241,8 @@
         <artifactId>maven-compiler-plugin</artifactId>
         <version>3.1</version>
         <configuration>
-          <source>1.6</source>
-          <target>1.6</target>
+          <source>1.7</source>
+          <target>1.7</target>
         </configuration>
       </plugin>
     </plugins>