SPARK-920 - JSON endpoint URI scheme part (spark://) duplicated
SPARK-921 - Add Application UI URL to ApplicationInfo Json output
Fixing SPARK-602: PythonPartitioner

Currently PythonPartitioner determines partition ID by hashing a
byte-array representation of PySpark's key. This PR lets
PythonPartitioner use the actual partition ID, which is required e.g.
for sorting via PySpark.
Merge pull request #33 from AndreSchumacher/pyspark_partition_key_change

Fixing SPARK-602: PythonPartitioner

Currently PythonPartitioner determines partition ID by hashing a
byte-array representation of PySpark's key. This PR lets
PythonPartitioner use the actual partition ID, which is required e.g.
for sorting via PySpark.
Merge pull request #27 from davidmccauley/master

SPARK-920/921 - JSON endpoint updates

920 - Removal of duplicate scheme part of Spark URI, it was appearing as spark://spark//host:port in the JSON field.

JSON now delivered as:
url:spark://127.0.0.1:7077

921 - Adding the URL of the Main Application UI will allow custom interfaces (that use the JSON output) to redirect from the standalone UI.