stdlib: improved Docker package

Signed-off-by: Solomon Hykes <sh.github.6811@hykes.org>

examples/dagger-dev/dev.cue

@@ -0,0 +1 @@
+../../dev.cue

examples/dagger-dev/main.cue

@@ -1,46 +0,0 @@
-package main
-
-// A dagger configuration to build and test the dagger source code.
-// This configuration can easily be adapted to build and test any go project.
-//
-//
-// Example:
-//   dagger compute ./examples/dagger-dev --input-dir repository=/path/to/go/project
-
-import (
-	"dagger.io/dagger"
-	"dagger.io/go"
-	"dagger.io/docker"
-)
-
-repository: dagger.#Artifact
-
-// Build `dagger` using Go
-build: go.#Build & {
-	source:   repository
-	packages: "./cmd/dagger"
-	output:   "/usr/local/bin/dagger"
-}
-
-// Run go tests
-test: go.#Test & {
-	source:   repository
-	packages: "./..."
-}
-
-// Run a command with the binary we just built
-help: docker.#Run & {
-	image: build
-	args: ["dagger", "-h"]
-}
-
-// Build dagger using the (included) Dockerfile
-buildWithDocker: docker.#Build & {
-	source: repository
-}
-
-// Run a command in the docker image we just built
-helpFromDocker: docker.#Run & {
-	image: buildWithDocker.image
-	args: ["dagger", "-h"]
-}