v2.2.0 - Build Networking

major refactor: broke build step out into its own file

we now parse the dockerfile and look for WAIT_FOR_WEAVE. if it exist we call to sauron and attach a network to it

v2.1.0

Includes ability to connect network before RUN commands

2.0.2

• rename layer.tar to just use the layer's hash ID
• fix race condition where layer.tar was being used before it existed