Seperate out CFSSL server components from cf_impl_cfssl

Currently CFSSL is automatically set up and run from ca_impl_cfssl.py

I think we should separate out the server components start_cfssl and stop_cfssl and instead just have the ip and port configurable and the operator runs their own cfssl instance wherever they like (it might be on a different host to the keylime_verifier), perhaps behind its own firewall etc. Either way I don’t think it should not be possible to run it separately.

In time we should also look to make CA’s plugable, so different PKI systems can be utilised.

@jetwhiz @nabilschear - any objections to the above? If not I will give it a key_feature label.

[nabilschear]

i think this sounds like a great idea. We were trying to make the cert support pluggable already, but it was mostly to fix the limitations of openssl (i.e., no crl support in m2crypto). A new look at what the interface should look like might be in order.

[THS-on]

#1012 removed CFSSL support.