error when using the user option to install

[yyzhang]

This issue is found by Marc Paterno -- only reported by yyzhang

When tying to install cluster_toolkit, here is the failure I get:

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$ git clone https://github.com/tmcclintock/cluster_toolkit.git $ cd cluster_toolkit/ $ python setup.py install --user running install error: can't combine user with prefix, exec_prefix/home, or install_(plat)base

Using the --user flag in order to reduce the likelihood of a collision between a system-wide installation and one's own account's stuff, and it would be nice if we can keep doing that.