[SPARK-1560]: Updated Pyrolite Dependency to be Java 6 compatible

Changed the Pyrolite dependency to a build which targets Java 6.

Author: Ahir Reddy <ahirreddy@gmail.com>

Closes #479 from ahirreddy/java6-pyrolite and squashes the following commits:

8ea25d3 [Ahir Reddy] Updated maven build to use java 6 compatible pyrolite
dabc703 [Ahir Reddy] Updated Pyrolite dependency to be Java 6 compatible

core/pom.xml

@@ -269,7 +269,7 @@
     <dependency>
       <groupId>org.spark-project</groupId>
       <artifactId>pyrolite</artifactId>
-      <version>2.0</version>
+      <version>2.0.1</version>
     </dependency>
   </dependencies>
   <build>

project/SparkBuild.scala

@@ -352,7 +352,7 @@ object SparkBuild extends Build {
         "com.twitter"                % "chill-java"       % chillVersion excludeAll(excludeAsm),
         "org.tachyonproject"         % "tachyon"          % "0.4.1-thrift" excludeAll(excludeHadoop, excludeCurator, excludeEclipseJetty, excludePowermock),
         "com.clearspring.analytics"  % "stream"           % "2.5.1" excludeAll(excludeFastutil),
-        "org.spark-project"          % "pyrolite"         % "2.0"
+        "org.spark-project"          % "pyrolite"         % "2.0.1"
       ),
     libraryDependencies ++= maybeAvro
   )