refactored how remotes work and how (some) config is loaded

plugin/remote/gitlab/register.go

@@ -1,16 +1,22 @@
 package gitlab
 
 import (
-	"os"
-
+	"github.com/drone/config"
 	"github.com/drone/drone/plugin/remote"
 )
 
-// registers the Gitlab plugin
-func init() {
-	var url = os.Getenv("GITLAB_URL")
-	if len(url) == 0 {
+var (
+	gitlabURL = config.String("gitlab-url", "")
+)
+
+// Registers the Gitlab plugin using the default
+// settings from the config file or environment
+// variables.
+func Register() {
+	if len(*gitlabURL) == 0 {
 		return
 	}
-	remote.Register(New(url))
+	remote.Register(
+		New(*gitlabURL),
+	)
 }