SPARK-1162 Added top in python.

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

Closes #93 from ScrapCodes/SPARK-1162/pyspark-top-takeOrdered and squashes the following commits:

ece1fa4 [Prashant Sharma] Added top in python.
SPARK-1160: Deprecate toArray in RDD

https://spark-project.atlassian.net/browse/SPARK-1160

reported by @mateiz: "It's redundant with collect() and the name doesn't make sense in Java, where we return a List (we can't return an array due to the way Java generics work). It's also missing in Python."

In this patch, I deprecated the method and changed the source files using it by replacing toArray with collect() directly

Author: CodingCat <zhunansjtu@gmail.com>

Closes #105 from CodingCat/SPARK-1060 and squashes the following commits:

286f163 [CodingCat] deprecate in JavaRDDLike
ee17b4e [CodingCat] add message and since
2ff7319 [CodingCat] deprecate toArray in RDD
Fix example bug: compile error

Author: jianghan <jianghan@xiaomi.com>

Closes #132 from pooorman/master and squashes the following commits:

54afbe0 [jianghan] Fix example bug: compile error
hot fix for PR105 - change to Java annotation

Author: CodingCat <zhunansjtu@gmail.com>

Closes #133 from CodingCat/SPARK-1160-2 and squashes the following commits:

6607155 [CodingCat] hot fix for PR105 - change to Java annotation