Otherwise, `sparkR.init()` with multiple `sparkPackages` results in this warning:
```
Warning message:
In if (packages != "") { :
the condition has length > 1 and only the first element will be used
```
Author: trestletech <jeff.allen@trestletechnology.net>
Closes#7701 from trestletech/compare-packages and squashes the following commits:
72c8b36 [trestletech] Correct function name.
c52db0e [trestletech] Added test for multiple packages.
3aab1a7 [trestletech] Use vector-friendly comparison for packages argument.
Author: Holden Karau <holden@pigscanfly.ca>
Closes#6928 from holdenk/SPARK-8506-sparkr-does-not-provide-an-easy-way-to-depend-on-spark-packages-when-performing-init-from-inside-of-r and squashes the following commits:
b60dd63 [Holden Karau] Add an example with the spark-csv package
fa8bc92 [Holden Karau] typo: sparm -> spark
865a90c [Holden Karau] strip spaces for comparision
c7a4471 [Holden Karau] Add some documentation
c1a9233 [Holden Karau] refactor for testing
c818556 [Holden Karau] Add pakages to R