Move installable packages to pkg

Still leaves some intermediate repos in `base/`

See #1266

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

pkg/init/Dockerfile

@@ -0,0 +1,12 @@
+FROM alpine:3.5
+
+RUN \
+  apk --no-cache update && \
+  apk --no-cache upgrade -a && \
+  apk --no-cache add \
+  dhcpcd \
+  e2fsprogs \
+  e2fsprogs-extra \
+  && rm -rf /var/cache/apk/*
+
+COPY . ./