Include the sbin/spark-config.sh in spark-executor

This is needed because broadcast values are broken on pyspark on Mesos, it tries to import pyspark but can't, as the PYTHONPATH is not set due to changes in ff5be9a4

https://issues.apache.org/jira/browse/SPARK-1725

Author: Bouke van der Bijl <boukevanderbijl@gmail.com>

Closes #651 from bouk/include-spark-config-in-mesos-executor and squashes the following commits:

b2f1295 [Bouke van der Bijl] Inline PYTHONPATH in spark-executor
eedbbcc [Bouke van der Bijl] Include the sbin/spark-config.sh in spark-executor
[SPARK-1755] Respect SparkSubmit --name on YARN

Right now, SparkSubmit ignores the `--name` flag for both yarn-client and yarn-cluster. This is a bug.

In client mode, SparkSubmit treats `--name` as a [cluster config](https://github.com/apache/spark/blob/master/core/src/main/scala/org/apache/spark/deploy/SparkSubmit.scala#L170) and does not propagate this to SparkContext.

In cluster mode, SparkSubmit passes this flag to `org.apache.spark.deploy.yarn.Client`, which only uses it for the [YARN ResourceManager](https://github.com/apache/spark/blob/master/yarn/stable/src/main/scala/org/apache/spark/deploy/yarn/Client.scala#L80), but does not propagate this to SparkContext.

This PR ensures that `spark.app.name` is always set if SparkSubmit receives the `--name` flag, which is what the usage promises. This makes it possible for applications to start a SparkContext with an empty conf `val sc = new SparkContext(new SparkConf)`, and inherit the app name from SparkSubmit.

Tested both modes on a YARN cluster.

Author: Andrew Or <andrewor14@gmail.com>

Closes #699 from andrewor14/yarn-app-name and squashes the following commits:

98f6a79 [Andrew Or] Fix tests
dea932f [Andrew Or] Merge branch 'master' of github.com:apache/spark into yarn-app-name
c86d9ca [Andrew Or] Respect SparkSubmit --name on YARN
[SPARK-1631] Correctly set the Yarn app name when launching the AM.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #539 from vanzin/yarn-app-name and squashes the following commits:

7d1ca4f [Marcelo Vanzin] [SPARK-1631] Correctly set the Yarn app name when launching the AM.