use ~/.config/dagger rather than ~/.dagger

since `.dagger` directories have a special meaning now because of gitflow,
it's better not to have a `~/.dagger` since it's not a workspace and
it confuses dagger (e.g. `dagger new` from $HOME).

We don't store state there anymore, just keys and the last version
check, so it's okay to be in ~/.config IMO

Looking at my system, in ~/.config there's `gcloud`, `gatsby`, `gh`,
`yarn`, and others so it seems like a pretty common location.

Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>

cmd/dagger/cmd/version.go

@@ -21,7 +21,7 @@ import (
 
 const (
 	defaultVersion = "devel"
-	versionFile    = "~/.dagger/version-check"
+	versionFile    = "~/.config/dagger/version-check"
 	versionURL     = "https://releases.dagger.io/dagger/latest_version"
 )
 
@@ -168,7 +168,7 @@ func checkVersion() {
 	baseDir := path.Dir(versionFilePath)
 
 	if _, err := os.Stat(baseDir); os.IsNotExist(err) {
-		if err := os.MkdirAll(baseDir, 0755); err != nil {
+		if err := os.MkdirAll(baseDir, 0700); err != nil {
 			// mkdir fails, ignore silently
 			return
 		}