[TD-3988]add mac test on Appveyor

.appveyor.yml

 version: 1.0.{build}
-os: Visual Studio 2015
+image: 
+  - Visual Studio 2015
+  - macos-mojave
 environment:
   matrix:
     - ARCH: amd64
     - ARCH: x86
+matrix:
+  exclude:
+    - image: macos-mojave
+      ARCH: x86
+for:
+  - 
+    matrix:
+      only:
+        - image: Visual Studio 2015
+    clone_folder: c:\dev\TDengine
+    clone_depth: 1
 
-clone_folder: c:\dev\TDengine
-clone_depth: 1
+    init:
+      - call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" %ARCH%
 
-init:
-  - call "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\vcvarsall.bat" %ARCH%
+    before_build:
+      - cd c:\dev\TDengine
+      - md build
 
-before_build:
-  - cd c:\dev\TDengine
-  - md build
-
-build_script:
-  - cd build
-  - cmake -G "NMake Makefiles" ..
-  - nmake install
+    build_script:
+      - cd build
+      - cmake -G "NMake Makefiles" ..
+      - nmake install
+  -
+    matrix:
+      only:
+        - image: macos-mojave
+    clone_depth: 1
 
+    build_script:
+      - mkdir debug
+      - cd debug
+      - cmake .. > /dev/null
+      - make > /dev/null
 notifications:
 - provider: Email
   to:
   - sangshuduo@gmail.com
-  
   on_build_success: true
   on_build_failure: true
   on_build_status_changed: true