[Windows][kinetic] Fix python_distutils_install.bat.in

[seanyen]

• Fix: PYTHONPATH isn't really passed to python setup.py by cmd /c /v method.
• Fix: For clean build, @CMAKE_INSTALL_PREFIX@\@PYTHON_INSTALL_DIR@ could not exist, so use mkdir to ensure the existence. (python_distutils_install.sh.in did the same thing.)
• Fix: move quotation from set ABC="xyz" to set "ABC=xyz" to avoid extra double quotes in the variable, otherwise, which subsequently caused problems for Python to parse the PYTHONPATH.

Here is the issue how does the problem manifest: ms-iot/ROSOnWindows#67

[dirk-thomas]

Thanks for the patch.

[seanyen]

Thanks!