[SPARK-4169] [Core] Accommodate non-English Locales in unit tests

For me the core tests failed because there are two locale dependent parts in the code.
Look at the Jira ticket for details.

Why is it necessary to check the exception message in isBindCollision in
https://github.com/apache/spark/blob/master/core/src/main/scala/org/apache/spark/util/Utils.scala#L1686
?

Author: Niklas Wilcke <1wilcke@informatik.uni-hamburg.de>

Closes #3036 from numbnut/core-test-fix and squashes the following commits:

1fb0d04 [Niklas Wilcke] Fixing locale dependend code and tests

(cherry picked from commit ed8bf1eac548577c4bbad7ce3f7f301a2f52ef17)
Signed-off-by: Andrew Or <andrew@databricks.com>
SPARK-2548 [STREAMING] JavaRecoverableWordCount is missing

Here's my attempt to re-port `RecoverableNetworkWordCount` to Java, following the example of its Scala and Java siblings. I fixed a few minor doc/formatting issues along the way I believe.

Author: Sean Owen <sowen@cloudera.com>

Closes #2564 from srowen/SPARK-2548 and squashes the following commits:

0d0bf29 [Sean Owen] Update checkpoint call as in https://github.com/apache/spark/pull/2735
35f23e3 [Sean Owen] Remove old comment about running in standalone mode
179b3c2 [Sean Owen] Re-port RecoverableNetworkWordCount to Java example, and touch up doc / formatting in related examples

(cherry picked from commit 3a02d416cd82a7a942fd6ff4a0e05ff070eb218a)
Signed-off-by: Tathagata Das <tathagata.das1565@gmail.com>