Author: Jon Maurer <tritab@gmail.com>
Author: Jonathan Maurer <jmaurer@Jonathans-MacBook-Pro.local>

Closes #10789 from tritab/cmd_updates.

[SPARK-11880][WINDOWS][SPARK SUBMIT] bin/load-spark-env.cmd loads spark-env.cmd from wrong directory

* On windows the `bin/load-spark-env.cmd` tries to load `spark-env.cmd` from `%~dp0..\..\conf`, where `~dp0` points to `bin` and `conf` is only one level up.
* Updated `bin/load-spark-env.cmd` to load `spark-env.cmd` from `%~dp0..\conf`, instead of `%~dp0..\..\conf`

Author: wangt <wangtao.upc@gmail.com>

Closes #9863 from toddwan/master.

added equivalent script to load-spark-env.sh

Author: Masayoshi TSUZUKI <tsudukim@oss.nttdata.co.jp>

Closes #5328 from tsudukim/feature/SPARK-6673 and squashes the following commits:

aaefb19 [Masayoshi TSUZUKI] removed dust.
be3405e [Masayoshi TSUZUKI] [SPARK-6673] spark-shell.cmd can't start in Windows even when spark was built