[SPARK-13843][STREAMING] Remove streaming-flume, streaming-mqtt, streaming-zeromq, streaming-akka, streaming-twitter to Spark packages

## What changes were proposed in this pull request?

Currently there are a few sub-projects, each for integrating with different external sources for Streaming.  Now that we have better ability to include external libraries (spark packages) and with Spark 2.0 coming up, we can move the following projects out of Spark to https://github.com/spark-packages

- streaming-flume
- streaming-akka
- streaming-mqtt
- streaming-zeromq
- streaming-twitter

They are just some ancillary packages and considering the overhead of maintenance, running tests and PR failures, it's better to maintain them out of Spark. In addition, these projects can have their different release cycles and we can release them faster.

I have already copied these projects to https://github.com/spark-packages

## How was this patch tested?

Jenkins tests

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #11672 from zsxwing/remove-external-pkg.

3 files changed, 1 insertions, 89 deletions

diff --git a/dev/audit-release/audit_release.py b/dev/audit-release/audit_release.py
index 4dabb51254..426b3117f1 100755
--- a/dev/audit-release/audit_release.py
+++ b/dev/audit-release/audit_release.py
@@ -116,8 +116,7 @@ original_dir = os.getcwd()
 # dependencies within those projects.
 modules = [
     "spark-core", "spark-mllib", "spark-streaming", "spark-repl",
-    "spark-graphx", "spark-streaming-flume", "spark-streaming-kafka",
-    "spark-streaming-mqtt", "spark-streaming-twitter", "spark-streaming-zeromq",
+    "spark-graphx", "spark-streaming-kafka",
     "spark-catalyst", "spark-sql", "spark-hive", "spark-streaming-kinesis-asl"
 ]
 modules = map(lambda m: "%s_%s" % (m, SCALA_BINARY_VERSION), modules)
diff --git a/dev/run-tests.py b/dev/run-tests.py
index a1e6f1bdb5..d940cdad3e 100755
--- a/dev/run-tests.py
+++ b/dev/run-tests.py
@@ -337,9 +337,6 @@ def build_spark_sbt(hadoop_version):
     build_profiles = get_hadoop_profiles(hadoop_version) + modules.root.build_profile_flags
     sbt_goals = ["package",
                  "streaming-kafka-assembly/assembly",
-                 "streaming-flume-assembly/assembly",
-                 "streaming-mqtt-assembly/assembly",
-                 "streaming-mqtt/test:assembly",
                  "streaming-kinesis-asl-assembly/assembly"]
     profiles_and_goals = build_profiles + sbt_goals
 
diff --git a/dev/sparktestsupport/modules.py b/dev/sparktestsupport/modules.py
index 1781de4c65..d1184886e2 100644
--- a/dev/sparktestsupport/modules.py
+++ b/dev/sparktestsupport/modules.py
@@ -210,43 +210,6 @@ streaming_kinesis_asl = Module(
 )
 
 
-streaming_zeromq = Module(
-    name="streaming-zeromq",
-    dependencies=[streaming],
-    source_file_regexes=[
-        "external/zeromq",
-    ],
-    sbt_test_goals=[
-        "streaming-zeromq/test",
-    ]
-)
-
-
-streaming_twitter = Module(
-    name="streaming-twitter",
-    dependencies=[streaming],
-    source_file_regexes=[
-        "external/twitter",
-    ],
-    sbt_test_goals=[
-        "streaming-twitter/test",
-    ]
-)
-
-
-streaming_mqtt = Module(
-    name="streaming-mqtt",
-    dependencies=[streaming],
-    source_file_regexes=[
-        "external/mqtt",
-        "external/mqtt-assembly",
-    ],
-    sbt_test_goals=[
-        "streaming-mqtt/test",
-    ]
-)
-
-
 streaming_kafka = Module(
     name="streaming-kafka",
     dependencies=[streaming],
@@ -260,51 +223,6 @@ streaming_kafka = Module(
 )
 
 
-streaming_flume_sink = Module(
-    name="streaming-flume-sink",
-    dependencies=[streaming],
-    source_file_regexes=[
-        "external/flume-sink",
-    ],
-    sbt_test_goals=[
-        "streaming-flume-sink/test",
-    ]
-)
-
-
-streaming_akka = Module(
-    name="streaming-akka",
-    dependencies=[streaming],
-    source_file_regexes=[
-        "external/akka",
-    ],
-    sbt_test_goals=[
-        "streaming-akka/test",
-    ]
-)
-
-
-streaming_flume = Module(
-    name="streaming-flume",
-    dependencies=[streaming],
-    source_file_regexes=[
-        "external/flume",
-    ],
-    sbt_test_goals=[
-        "streaming-flume/test",
-    ]
-)
-
-
-streaming_flume_assembly = Module(
-    name="streaming-flume-assembly",
-    dependencies=[streaming_flume, streaming_flume_sink],
-    source_file_regexes=[
-        "external/flume-assembly",
-    ]
-)
-
-
 mllib = Module(
     name="mllib",
     dependencies=[streaming, sql],
@@ -376,8 +294,6 @@ pyspark_streaming = Module(
         pyspark_core,
         streaming,
         streaming_kafka,
-        streaming_flume_assembly,
-        streaming_mqtt,
         streaming_kinesis_asl
     ],
     source_file_regexes=[