add mac build to drone

.drone.yml

@@ -1,10 +1,32 @@
 ---
 kind: pipeline
 type: docker
-name: default
+name: linux-build
 
 steps:
-- name: wow-ci
+- name: linux-build
   image: wow-dependencies:v1.0
   commands:
   - make -j2 release-static-linux-x86_64
+
+---
+kind: pipeline
+type: ssh
+name: mac-build
+
+server:
+  host:
+    from_secret: mac-server
+  user:
+    from_secret: mac-user
+  ssh_key:
+    from_secret: ssh-key
+
+steps:
+- name: mac-build
+  commands:
+  - /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install.sh)"
+  - export PATH=/usr/local/bin:$PATH
+  - brew update
+  - brew bundle --file=contrib/brew/Brewfile
+  - make -j3 release-static