Add python x64 on Appveyor

Signed-off-by: Uilian Ries <uilianries@gmail.com>

Author: uilianries

appveyor.yml

@@ -1,13 +1,24 @@
 build: false
 
 environment:
-    PYTHON_ARCH: "32"
 
     matrix:
         - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
           PYTHON: "C:\\Python27"
+          PYTHON_ARCH: "32"
+          PYTHON_VERSION: "2.7.x"
+        - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+          PYTHON: "C:\\Python27-x64"
+          PYTHON_ARCH: "64"
+          PYTHON_VERSION: "2.7.x"
         - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
           PYTHON: "C:\\Python38"
+          PYTHON_ARCH: "32"
+          PYTHON_VERSION: "3.8.x"
+        - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
+          PYTHON: "C:\\Python38-x64"
+          PYTHON_ARCH: "64"
+          PYTHON_VERSION: "3.8.x"
 
 test_script:
 - python tests/run_tests.py