PKCS#12 certificates no longer used

All certificates are inlined into the `customer.conf` file now.

Not sure what this means for the `-beescloud.json` and `-cloudbees-clc.json`; are these files still meaningful?

For the `-demo.json`, the patch may just work, but then again the code that _appends_ to `customer.conf` may need to be changed to _prepend_ to it; I am not sure if OpenVPN allows you to add directives after inlined certificates.