Mount CWD as something other than /workspace in the container

[seanpmorgan]

It's been mentioned that it's a bit un-intuitive for those familiar with docker that host CWD becomes /workspace inside the container. Simply re-naming this directory to /host_cwd would be more explicit as to what is going on and prevent confusion.

[shenshaw26]

This is OBE and will be dealt with in: https://github.com/shenshaw26/armory/pull/6. armory bits will be in /armory-repo/ in the docker containers going forward.

[mwartell]

Better documentation of container interfaces would help here.