Expects storage driver executables to be of the form registry-storage-name

Moves main packages to sub-packages of the individual storage drivers

cmd/registry-storagedriver-inmemory/main.go

@@ -0,0 +1,12 @@
+package main
+
+import (
+	"github.com/docker/docker-registry/storagedriver/inmemory"
+	"github.com/docker/docker-registry/storagedriver/ipc"
+)
+
+// An out-of-process inmemory driver, intended to be run by ipc.NewDriverClient
+// This exists primarily for example and testing purposes
+func main() {
+	ipc.StorageDriverServer(inmemory.New())
+}