Update branch metadata

2.18.x has been created, so:

- 2.16.x is no longer maintained;
- 2.17.x becomes the current branch;
- 2.18.x is the next minor branch.

Author: greg0ire

.doctrine-project.json

@@ -10,16 +10,22 @@
       "slug": "latest",
       "upcoming": true
     },
+    {
+      "name": "2.18",
+      "branchName": "2.18.x",
+      "slug": "2.18",
+      "upcoming": true
+    },
     {
       "name": "2.17",
       "branchName": "2.17.x",
       "slug": "2.17",
-      "upcoming": true
+      "current": true
     },
     {
       "name": "2.16",
       "slug": "2.16",
-      "current": true
+      "maintained": false
     },
     {
       "name": "2.15",

.symfony.bundle.yaml

@@ -12,9 +12,10 @@ branches:
     - "2.15.x"
     - "2.16.x"
     - "2.17.x"
+    - "2.18.x"
 maintained_branches:
-    - "2.16.x"
     - "2.17.x"
+    - "2.18.x"
 doc_dir: "docs/en/"
-current_branch: "2.16.x"
-dev_branch: "2.17.x"
+current_branch: "2.17.x"
+dev_branch: "2.18.x"