Replace links with Docker 1.9 bridge networks

[jawher]

Bazooka used to rely on links to work:

• The DB container was linked into the server container
• The server container was linked into the web container

This PR proposes to replace these links (which are to be considered a deprecated and legacy feature in Docker) with the usage of bridge networks:

bzk service start will create a bzk_net network if it doesn't exist, and attach the db, server and containers to it for them to be able to communicate.

The build flow was also modified so that the various build containers (orchestration, parser, ...) are attached to the same network when started.

This PR also adds:

• a working docker compose config capable of starting bazooka using docker compose
• a crowdr config
• a capitan config

[jawher]

Note: This PR depends on a proposed PR to go-dockercommand: https://github.com/bywan/go-dockercommand/pull/13

[julienvey]

LGTM :+1: Tested and works fine.

Will need to document installation options