[MINOR][DOCS] Fix th doc. of spark-streaming with kinesis

[maropu]

What changes were proposed in this pull request?

This pr is just to fix the document of spark-kinesis-integration.
Since SPARK-17418 prevented all the kinesis stuffs (including kinesis example code)
from publishing, bin/run-example streaming.KinesisWordCountASL and bin/run-example streaming.JavaKinesisWordCountASL does not work.
Instead, it fetches the kinesis jar from the Spark Package.

[SparkQA]

Test build #65962 has finished for PR 15260 at commit ce4640e.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[srowen]

Although it should still work (?) to build with -Pkinesis-asl I think, because the assembly still exists it's just not published, I do think we should make this doc change, because it reflects how users would really use this with a Spark distribution.

[maropu]

In master, I tried;

$ mvn -Pkinesis-asl -DskipTests package; ./bin/run-example streaming.KinesisWordCountASL
java.lang.ClassNotFoundException: org.apache.spark.examples.streaming.KinesisWordCountASL
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method

Also, in the spark-2.0 branch, I hit the same issue.
IIUC classpath does not include the kinesis jar in external/kinesis-asl-assembly/target when running this example.

[maropu]

Aha, I see. However, some users possibly think they'd just like to download compiled Spark jars and run the kinesis example for quick tests because compiling the whole spark package takes much time.
In other examples (e.g., SparkPi), since spark compiled binaries in the download site bundle them, we can download them and just run the examples. But, we currently cannot run the kinesis example because they donot bundle it now.

So, how about staying this current doc as it is and appending a new direction like this pr?
Also, in a follow-up pr, it is okay to me that I'll fix the run-example script so that it can add external/kinesis-asl-assembly/target in classpath.

[srowen]

I think your current change sounds fine. It shows how people should use this now.

[maropu]

yea, thx,
Also, should we add external/kinesis-asl-assembly/target in classpath so that we can run $ mvn -Pkinesis-asl -DskipTests package; ./bin/run-example streaming.KinesisWordCountASL?

[srowen]

Oh, add it to run-example? I see why you say that although it won't be necessary for people using it the 'right way' and the docs will now show that way.

[maropu]

yea, okay.

[srowen]

Merged to master/2.0