Add PullApprove settings file (copied from core repo) (#23)

.pullapprove.yml

@@ -0,0 +1,37 @@
+version: 2
+
+always_pending:
+  title_regex: '(WIP|wip)'
+  labels:
+    - wip
+  explanation: 'This PR is a work in progress...'
+
+group_defaults:
+  reset_on_push:
+    enabled: true
+  reject_value: -2
+  approve_regex: '^(Approved|:shipit:|:\+1:|Engage)'
+  reject_regex: '^(Rejected|:-1:|Borg)'
+  author_approval:
+    auto: true
+
+groups:
+  development:
+    approve_by_comment:
+      enabled: true
+    conditions:
+      branches:
+        - development
+    required: 2
+    teams:
+      - approvers
+
+  master:
+    approve_by_comment:
+      enabled: true
+    conditions:
+      branches:
+        - master
+    required: 4
+    teams:
+      - admin