rename volume volid to file to better represent the meaning,

add raw value string to devices,
fix JSON to go naming for device_name vendor_name ... in devices,
bump API version to 0.03

app/app.go

@@ -13,7 +13,7 @@ import (
 	"github.com/luthermonson/go-proxmox"
 )
 
-const APIVersion string = "0.0.2"
+const APIVersion string = "0.0.3"
 
 var client ProxmoxClient