Revert "SPARK-5607: Update to Kryo 2.24.0 to avoid including objenesis 1.2."

This reverts commit c3b8d27.

Author: pwendell

pom.xml

@@ -137,7 +137,6 @@
     <jetty.version>8.1.14.v20131031</jetty.version>
     <orbit.version>3.0.0.v201112011016</orbit.version>
     <chill.version>0.5.0</chill.version>
-    <kryo.version>2.24.0</kryo.version>
     <ivy.version>2.4.0</ivy.version>
     <oro.version>2.0.8</oro.version>
     <codahale.metrics.version>3.1.0</codahale.metrics.version>
@@ -342,13 +341,7 @@
           </exclusion>
         </exclusions>
       </dependency>
-      <!-- Bump kryo version (included via chill) due to SPARK-5607 -->
-      <dependency>
-        <groupId>com.esotericsoftware.kryo</groupId>
-        <artifactId>kryo</artifactId>
-        <version>${kryo.version}</version>
-      </dependency>
-
+ 
       <!-- Shaded deps marked as provided. These are promoted to compile scope
            in the modules where we want the shaded classes to appear in the
            associated jar. -->