SPARK-1996. Remove use of special Maven repo for Akka

Just following up Matei's suggestion to remove the Akka repo references. Builds and the audit-release script appear OK.

Author: Sean Owen <sowen@cloudera.com>

Closes #1170 from srowen/SPARK-1996 and squashes the following commits:

5ca2930 [Sean Owen] Remove outdated Akka repository references

dev/audit-release/blank_maven_build/pom.xml

@@ -28,10 +28,6 @@
       <id>Spray.cc repository</id>
       <url>http://repo.spray.cc</url>
     </repository>
-    <repository>
-      <id>Akka repository</id>
-      <url>http://repo.akka.io/releases</url>
-    </repository>
     <repository>
       <id>Spark Staging Repo</id>
       <url>${spark.release.repository}</url>

dev/audit-release/blank_sbt_build/build.sbt

@@ -25,5 +25,4 @@ libraryDependencies += "org.apache.spark" % System.getenv.get("SPARK_MODULE") %
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

dev/audit-release/maven_app_core/pom.xml

@@ -28,10 +28,6 @@
       <id>Spray.cc repository</id>
       <url>http://repo.spray.cc</url>
     </repository>
-    <repository>
-      <id>Akka repository</id>
-      <url>http://repo.akka.io/releases</url>
-    </repository>
     <repository>
       <id>Spark Staging Repo</id>
       <url>${spark.release.repository}</url>

dev/audit-release/sbt_app_core/build.sbt

@@ -25,5 +25,4 @@ libraryDependencies += "org.apache.spark" %% "spark-core" % System.getenv.get("S
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

dev/audit-release/sbt_app_ganglia/build.sbt

@@ -27,5 +27,4 @@ libraryDependencies += "org.apache.spark" %% "spark-ganglia-lgpl" % System.geten
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

dev/audit-release/sbt_app_graphx/build.sbt

@@ -25,5 +25,4 @@ libraryDependencies += "org.apache.spark" %% "spark-graphx" % System.getenv.get(
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

dev/audit-release/sbt_app_hive/build.sbt

@@ -25,5 +25,4 @@ libraryDependencies += "org.apache.spark" %% "spark-hive" % System.getenv.get("S
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

dev/audit-release/sbt_app_sql/build.sbt

@@ -25,5 +25,4 @@ libraryDependencies += "org.apache.spark" %% "spark-sql" % System.getenv.get("SP
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

dev/audit-release/sbt_app_streaming/build.sbt

@@ -25,5 +25,4 @@ libraryDependencies += "org.apache.spark" %% "spark-streaming" % System.getenv.g
 
 resolvers ++= Seq(
   "Spark Release Repository" at System.getenv.get("SPARK_RELEASE_REPOSITORY"),
-  "Akka Repository" at "http://repo.akka.io/releases/",
   "Spray Repository" at "http://repo.spray.cc/")

docs/quick-start.md

@@ -266,8 +266,6 @@ version := "1.0"
 scalaVersion := "{{site.SCALA_VERSION}}"
 
 libraryDependencies += "org.apache.spark" %% "spark-core" % "{{site.SPARK_VERSION}}"
-
-resolvers += "Akka Repository" at "http://repo.akka.io/releases/"
 {% endhighlight %}
 
 For sbt to work correctly, we'll need to layout `SimpleApp.scala` and `simple.sbt`
@@ -349,12 +347,6 @@ Note that Spark artifacts are tagged with a Scala version.
   <name>Simple Project</name>
   <packaging>jar</packaging>
   <version>1.0</version>
-  <repositories>
-    <repository>
-      <id>Akka repository</id>
-      <url>http://repo.akka.io/releases</url>
-    </repository>
-  </repositories>
   <dependencies>
     <dependency> <!-- Spark dependency -->
       <groupId>org.apache.spark</groupId>