Add mostly self-contained bootstrapping with testing in Docker.

This commit adds several things:

1. in_docker, which runs arbitrary commands in a Docker environment that
consists of the OS of your choice, the crowbar core repository mounted
in that container at /opt/opencrowbar/core, and port forwarding of port
3000 from localhost to the container.  in_docker is also pretty smart
about honoring your local http proxy settings.

2. A shiny new bootstrap directory that has the goal of bootstrapping a
system into  somthing capable of running OpenCrowbar in either
development or production mode.  It is still quite rough, but I have
been able to get the Crowbar web UI up and running in development and
production modes from it.

3. A bunch of tweaks to fix up bugs found making 2 work.

How to use it:

To run CB in development mode:
./in_docker ubuntu ./development.sh

To run in production mode:
./in_docker ubuntu ./production.sh

Further work:

1. Tweak the network barclamp to play nice with having the admin node
run in a Docker container.

2. Test the bootstrap infrastructure in a full-fledged VM.

3. Add support for something besides the core.

4. Make opensuse 13.1, fedora-20, and centos-6.5 actually work.