Arrow no longer a dependency in PythonRDD

Author: BryanCutler

core/pom.xml

@@ -33,10 +33,6 @@
   <name>Spark Project Core</name>
   <url>http://spark.apache.org/</url>
   <dependencies>
-    <dependency>
-      <groupId>org.apache.arrow</groupId>
-      <artifactId>arrow-vector</artifactId>
-    </dependency>
     <dependency>
       <groupId>org.apache.avro</groupId>
       <artifactId>avro-mapred</artifactId>