Create mounted volumes before running docker

If we mount to a directory the doesn't exist, docker will create the
local directory.

If we let docker create the directories, it will create it owned
by root-user, and then the container won't be able to write to the
directory.
By creating them in-advance, we make them owned by the user, and the
container can write to them.

BTW - This solves the problem with 'go build' not being able to write to
the 'gocache' directory.

Mount .gitconfig to build container (Stratoscale#109)

This is so that tools inside the container can push code up
to github.

Mount .gitconfig to build container (Stratoscale#109)

This is so that tools inside the container can push code up
to github.

fixed import

skipper.yaml spec: enable list type for environment variables

When environment variables are give as list:
  * If a=b, add key a with value b to the docker environment variables.
  * If only a key is given, add it to the docker environment variables if exists in
    the host environment variables.

Merge pull request Stratoscale#104 from Stratoscale/allow-no-git

Don't fail when not working in a git repository

Enable access to git using the user credentials

Added mount of ~/.netrc
Set HOME to the user $HOME

Tag build container image

Retry on destroy network

Diffuse KEEP_IMAGES environment