install.py does not handle installer tar path with spaces

[Matthias Homann]

Found a minor bug in the setup.py script if used with local installer tar file option.

If the tar file is in a different folder which has white spaces in the path, then the installation fails because the pip command can't find the file. The fix is simply to insert quotation marks around the installer file in the pip command.

Line 1627 in installer.py version 0.2.1, current code:
    cmd = make_pip_command(
        'install --user --disable-pip-version-check --no-deps {}'.format(installer)
    )

Improved code:
    cmd = make_pip_command(
        'install --user --disable-pip-version-check --no-deps "{}"'.format(installer)
    )