create dockerfile for fabric-ccenv-sgx

[mbrandenburger]

Currently, our sgx-enabled docker image fabric-ccenv-sgx depends on https://github.com/tozd/docker-sgx. Thanks again for providing this! However, a recent updated led to errors when building the docker image as reported in #29.

We should provide and maintain or own docker file.

@g2flyer has suggested:

For more long-term i propose we eventually dump docker-sgx and go with our own. We could already use the one from PDO but probably better would be to do the switch once i have a docker image for DCAP (which still supports epid) which i plan to do for PDO and try to do it also in a way that it would be easy shareable/copyable for TCC ...

[mbrandenburger]

This task also refers to #15 to enable support for DCAP

[mbrandenburger]

closed with #168