Please adjust setup.py to use /usr/local areas instead of /usr ones

[vkuznet]

On OSX the /usr area is protected by SIP (System Integrity Protection) and there your setup.py fails to install the package. What needs to be changed is /usr to /usr/local area in setup.py, e.g.
https://github.com/scitokens/x509-scitokens-issuer/blob/master/setup.py#L17-18

I also not sure about /etc/httpd and /etc/x509-scitokens-issuer locations since the end-user may not have ability to install in these areas either. May be it would be easier to make appropriate configuration option with these defaults.

[vkuznet]

The patch is here: #6