[SPARK-7997][CORE] Remove Akka from Spark Core and Streaming

- Remove Akka dependency from core. Note: the streaming-akka project still uses Akka.
- Remove HttpFileServer
- Remove Akka configs from SparkConf and SSLOptions
- Rename `spark.akka.frameSize` to `spark.rpc.message.maxSize`. I think it's still worth to keep this config because using `DirectTaskResult` or `IndirectTaskResult`  depends on it.
- Update comments and docs

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #10854 from zsxwing/remove-akka.

1 files changed, 5 insertions, 0 deletions

diff --git a/pom.xml b/pom.xml
index 43f08efaae..f08642f606 100644
--- a/pom.xml
+++ b/pom.xml
@@ -570,6 +570,11 @@
         <version>4.0.29.Final</version>
       </dependency>
       <dependency>
+        <groupId>io.netty</groupId>
+        <artifactId>netty</artifactId>
+        <version>3.8.0.Final</version>
+      </dependency>
+      <dependency>
         <groupId>org.apache.derby</groupId>
         <artifactId>derby</artifactId>
         <version>${derby.version}</version>