[SPARK-19232][SPARKR] Update Spark distribution download cache location on Windows
[SPARK-19232][SPARKR] Update Spark distribution download cache location on Windows

## What changes were proposed in this pull request?

Windows seems to be the only place with appauthor in the path, for which we should say "Apache" (and case sensitive)
Current path of `AppData\Local\spark\spark\Cache` is a bit odd.

## How was this patch tested?

manual.

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #16590 from felixcheung/rcachedir.

(cherry picked from commit a115a54399cd4bedb1a5086943a88af6339fbe85)
Signed-off-by: Shivaram Venkataraman <ad63b47dfac1951bde2b661ba9fbbe123f686bee@cs.berkeley.edu>

big-pegasus/spark,SnappyDataInc/spark,SnappyDataInc/spark,big-pegasus/spark,big-pegasus/spark,SnappyDataInc/spark,big-pegasus/spark,big-pegasus/spark,big-pegasus/spark,SnappyDataInc/spark,SnappyDataInc/spark,SnappyDataInc/spark,big-pegasus/spark,SnappyDataInc/spark