[SPARK-1398] Removed findbugs jsr305 dependency

Should be a painless upgrade, and does offer some significant advantages should we want to leverage FindBugs more during the 1.0 lifecycle. http://findbugs.sourceforge.net/findbugs2.html

Author: Mark Hamstra <markhamstra@gmail.com>

Closes #307 from markhamstra/findbugs and squashes the following commits:

99f2d09 [Mark Hamstra] Removed unnecessary findbugs jsr305 dependency

core/pom.xml

@@ -82,10 +82,6 @@
       <groupId>com.google.guava</groupId>
       <artifactId>guava</artifactId>
     </dependency>
-    <dependency>
-      <groupId>com.google.code.findbugs</groupId>
-      <artifactId>jsr305</artifactId>
-    </dependency>
     <dependency>
       <groupId>org.slf4j</groupId>
       <artifactId>slf4j-api</artifactId>

pom.xml

@@ -214,11 +214,6 @@
         <artifactId>guava</artifactId>
         <version>14.0.1</version>
       </dependency>
-      <dependency>
-        <groupId>com.google.code.findbugs</groupId>
-        <artifactId>jsr305</artifactId>
-        <version>1.3.9</version>
-      </dependency>
       <dependency>
         <groupId>org.slf4j</groupId>
         <artifactId>slf4j-api</artifactId>

project/SparkBuild.scala

@@ -296,7 +296,6 @@ object SparkBuild extends Build {
     name := "spark-core",
     libraryDependencies ++= Seq(
         "com.google.guava"           % "guava"            % "14.0.1",
-        "com.google.code.findbugs"   % "jsr305"           % "1.3.9",
         "log4j"                      % "log4j"            % "1.2.17",
         "org.slf4j"                  % "slf4j-api"        % slf4jVersion,
         "org.slf4j"                  % "slf4j-log4j12"    % slf4jVersion,