Fix bug in SparkLoadTask for `CACHE <partitioned_table>`

Each partition would result in a new partitioned table entry ...
Allow users to control the number of tasks for table scan operations
This will enable user's queries to perform well even for high cardinality partitioned tables
Merge pull request #305 from sundeepn/coalesce

Allow users to control the number of tasks for table scan operations
Merge pull request #296 from harveyfeng/master

Fix bug in SparkLoadTask for `CACHE <partitioned_table>`
Update Spark repo path
Fix issue with SCALA_VERSION in run-tests-from-scratch
Add option to run all Hive tests.
Add split tests capability to run-tests-from-scratch
Re-add all tests file from Hive-11 and option to run them in run-tests-from-scratch
Fix issue with reading tests from TEST_FILE in TestSharkCliDriver
Add ptest2_shark - framework for parallel testing