feat: add utility to print list of supported resources (#112)

Co-authored-by: Evan Nemerson <[email protected]>

cmd/list_resources/README.md

@@ -0,0 +1,6 @@
+# List Resources
+
+The AWS provider is very old, and unfortunately some libraries it uses were
+changed in backwards incompatible ways.  To avoid linking with this, instead of
+providing an interface in code we provide a command which generates a list of
+types.

cmd/list_resources/main.go

@@ -0,0 +1,28 @@
+package main
+
+import (
+	"encoding/json"
+	"os"
+
+	"github.com/hashicorp/terraform-provider-aws/internal/provider"
+)
+
+type TypesList struct {
+	Types []string
+}
+
+func main() {
+	pi := provider.Provider()
+
+	types := TypesList{}
+	for k := range pi.ResourcesMap {
+		types.Types = append(types.Types, k)
+	}
+
+	data, err := json.MarshalIndent(types, "", "  ")
+	if err != nil {
+		panic(err)
+	}
+
+	os.Stdout.Write(data)
+}