SPARK-1851. Upgrade Avro dependency to 1.7.6 so Spark can read Avro file...

...s

Author: Sandy Ryza <sandy@cloudera.com>

Closes #795 from sryza/sandy-spark-1851 and squashes the following commits:

79c8227 [Sandy Ryza] SPARK-1851. Upgrade Avro dependency to 1.7.6 so Spark can read Avro files

pom.xml

@@ -129,7 +129,7 @@
     <jetty.version>8.1.14.v20131031</jetty.version>
     <chill.version>0.3.6</chill.version>
     <codahale.metrics.version>3.0.0</codahale.metrics.version>
-    <avro.version>1.7.4</avro.version>
+    <avro.version>1.7.6</avro.version>
     <jets3t.version>0.7.1</jets3t.version>
 
     <PermGen>64m</PermGen>