This reverts commit 0e8b3107.

Reason for revert: wrappers aren't being created in python2-bin, other disruptions

Original change's description:
> Remove py batch wrappers from root dir
>
> This removes python.bat and python3.bat batch wrappers from root of this
> repository. This change brings Windows set up closer to unix.
>
> depot_tools provides batch wrappers in python-bin and python2-bin
> directories and user can opt in to use it by adding them to PATH.
>
> Bug: 777069
> Change-Id: Ie7571a49f940e7a69b6c18779499c39aee94d06a
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2742181
> Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
> Reviewed-by: Dirk Pranke <dpranke@google.com>
> Commit-Queue: Josip Sokcevic <sokcevic@google.com>

Bug: 777069
Change-Id: Ieaadb032249fa5d6eea39668355c0c7de06dfbeb
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2747702
Auto-Submit: Dirk Pranke <dpranke@google.com>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>