SPARK-1565, update examples to be used with spark-submit script.

Commit for initial feedback, basically I am curious if we should prompt user for providing args esp. when its mandatory. And can we skip if they are not ?

Also few other things that did not work like
`bin/spark-submit examples/target/scala-2.10/spark-examples-1.0.0-SNAPSHOT-hadoop1.0.4.jar --class org.apache.spark.examples.SparkALS --arg 100 500 10 5 2`

Not all the args get passed properly, may be I have messed up something will try to sort it out hopefully.

Author: Prashant Sharma <prashant.s@imaginea.com>

Closes #552 from ScrapCodes/SPARK-1565/update-examples and squashes the following commits:

669dd23 [Prashant Sharma] Review comments
2727e70 [Prashant Sharma] SPARK-1565, update examples to be used with spark-submit script.
[SPARK-1745] Move interrupted flag from TaskContext constructor (minor)

It makes little sense to start a TaskContext that is interrupted. Indeed, I searched for all use cases of it and didn't find a single instance in which `interrupted` is true on construction.

This was inspired by reviewing #640, which adds an additional `@volatile var completed` that is similar. These are not the most urgent changes, but I wanted to push them out before I forget.

Author: Andrew Or <andrewor14@gmail.com>

Closes #675 from andrewor14/task-context and squashes the following commits:

9575e02 [Andrew Or] Add space
69455d1 [Andrew Or] Merge branch 'master' of github.com:apache/spark into task-context
c471490 [Andrew Or] Oops, removed one flag too many. Adding it back.
85311f8 [Andrew Or] Move interrupted flag from TaskContext constructor
Fixing typo in als.py

XtY should be Xty.

Author: Evan Sparks <evan.sparks@gmail.com>

Closes #696 from etrain/patch-2 and squashes the following commits:

634cb8d [Evan Sparks] Fixing typo in als.py
[SPARK-1754] [SQL] Add missing arithmetic DSL operations.

Add missing arithmetic DSL operations: `unary_-`, `%`.

Author: Takuya UESHIN <ueshin@happy-camper.st>

Closes #689 from ueshin/issues/SPARK-1754 and squashes the following commits:

a09ef69 [Takuya UESHIN] Add also missing ! (not) operation.
f73ae2c [Takuya UESHIN] Remove redundant tests.
5b3f087 [Takuya UESHIN] Add tests relating DSL operations.
e09c5b8 [Takuya UESHIN] Add missing arithmetic DSL operations.
MLlib documentation fix

Fixed the documentation for that `loadLibSVMData` is changed to `loadLibSVMFile`.

Author: DB Tsai <dbtsai@alpinenow.com>

Closes #703 from dbtsai/dbtsai-docfix and squashes the following commits:

71dd508 [DB Tsai] loadLibSVMData is changed to loadLibSVMFile
[SPARK-1157][MLlib] Bug fix: lossHistory should exclude rejection steps, and remove miniBatch

Getting the lossHistory from Breeze's API which already excludes the rejection steps in line search. Also, remove the miniBatch in LBFGS since those quasi-Newton methods approximate the inverse of Hessian. It doesn't make sense if the gradients are computed from a varying objective.

Author: DB Tsai <dbtsai@alpinenow.com>

Closes #582 from dbtsai/dbtsai-lbfgs-bug and squashes the following commits:

9cc6cf9 [DB Tsai] Removed the miniBatch in LBFGS.
1ba6a33 [DB Tsai] Formatting the code.
d72c679 [DB Tsai] Using Breeze's states to get the loss.
Bug fix of sparse vector conversion

Fixed a small bug caused by the inconsistency of index/data array size and vector length.

Author: Funes <tianshaocun@gmail.com>
Author: funes <tianshaocun@gmail.com>

Closes #661 from funes/bugfix and squashes the following commits:

edb2b9d [funes] remove unused import
75dced3 [Funes] update test case
d129a66 [Funes] Add test for sparse breeze by vector builder
64e7198 [Funes] Copy data only when necessary
b85806c [Funes] Bug fix of sparse vector conversion