Upgrade branch 2.6.x using TemplateControl (playframework#64)

```
Updated with template-control on 2018-11-29T15:43:16.396Z
  /.mergify.yml:
    wrote /.mergify.yml

```

.mergify.yml

@@ -0,0 +1,57 @@
+pull_request_rules:
+  - name: automatic merge on CI success require review
+    conditions:
+      - status-success=continuous-integration/travis-ci/pr
+      - "#approved-reviews-by>=1"
+      - "#changes-requested-reviews-by=0"
+      - label=merge-when-green
+      - label!=block-merge
+    actions:
+      merge:
+        method: squash
+        strict: smart
+
+  - name: automatic merge on CI success for TemplateControl
+    conditions:
+      - status-success=continuous-integration/travis-ci/pr
+      - label=merge-when-green
+      - label=template-control
+      - label!=block-merge
+    actions:
+      merge:
+        method: squash
+        strict: smart
+
+  # delete any branch when already merged
+  # doesn't matter if marked with labels or not
+  - name: delete branch after merge
+    conditions:
+      - merged
+    actions:
+      delete_head_branch: {}
+
+  # delete 'merge-when-green' label if present and merged
+  - name: remove label after merge
+    conditions:
+      - merged
+      - label=merge-when-green
+    actions:
+      label:
+        remove: [merge-when-green]
+
+  # delete 'template-control' label if present and merged
+  - name: remove label after merge
+    conditions:
+      - merged
+      - label=template-control
+    actions:
+      label:
+        remove: [template-control]
+
+  - name: auto add wip
+    conditions:
+      # match a few flavours of wip
+      - title~=^(\[wip\]( |:) |\[WIP\]( |:) |wip( |:) |WIP( |:)).*
+    actions:
+      label:
+        add: ["block-merge"]

.travis.yml

@@ -6,8 +6,6 @@ scala:
 - 2.12.6
 jdk:
 - oraclejdk8
-- oraclejdk9
-- oraclejdk10
 - oraclejdk11
 env:
   matrix:
@@ -27,11 +25,8 @@ before_cache:
 # Exclude some combinations from build matrix. See:
 # https://docs.travis-ci.com/user/customizing-the-build/#Build-Matrix
 matrix:
+  fast_finish: true
   exclude:
-    - scala: 2.11.12
-      jdk: oraclejdk9
-    - scala: 2.11.12
-      jdk: oraclejdk10
     - scala: 2.11.12
       jdk: oraclejdk11
   allow_failures:

build.sbt

@@ -6,7 +6,7 @@ name := """play-chatroom-scala-example"""
 
 version := "2.6.x"
 
-scalaVersion := "2.12.6"
+scalaVersion := "2.12.7"
 
 crossScalaVersions := Seq("2.11.12", "2.12.4")