[SPARKR-144] Implement saveAsTextFile() in the RDD class.
Sort lists before comparing in unit tests
Since Spark doesn't guarantee that shuffle results will always
be in the same order, we need to sort the results before comparing
for deterministic behavior
Refactor RRDD code.
Merge remote-tracking branch 'SparkR_upstream/master' into saveAsTextFile
Merge pull request #118 from sun-rui/saveAsTextFile

[SPARKR-144] Implement saveAsTextFile() in the RDD class.
Merge branch 'master' of https://github.com/amplab-extras/SparkR-pkg into fix-sort-order
Fix saveAsTextFile test case
Merge pull request #121 from shivaram/fix-sort-order

[SPARKR-143] Sort lists before comparing in unit tests
Merge remote-tracking branch 'upstream/master'