Build 32 and 64 bit version

appveyor.yml

@@ -1,6 +1,15 @@
 version: 1.0.{build}
 image: Visual Studio 2015
 configuration: Release
+  matrix:
+  - ARCH: 32
+    GENERATOR: '"Visual Studio 11"'
+    PYTHON: '"C:\Python35\python.exe"'
+    PIP: '"C:\Python35\Scripts\pip.exe"'
+  - ARCH: 64
+    GENERATOR: '"Visual Studio 11 Win64"'
+    PYTHON: '"C:\Python35-x64\python.exe"'
+    PIP: '"C:\Python35-x64\Scripts\pip.exe"'
 build_script:
 - cmd: |
     set LIBGIT2=%APPVEYOR_BUILD_FOLDER%\build\libgit2
@@ -8,12 +17,12 @@ build_script:
     mkdir build
     
     cd build
-    cmake -DSTDCALL=OFF -DBUILD_CLAR=OFF -DCMAKE_INSTALL_PREFIX=%LIBGIT2% ../libgit2 -G"Visual Studio 11 Win64"
+    cmake -DSTDCALL=OFF -DBUILD_CLAR=OFF -DCMAKE_INSTALL_PREFIX=%LIBGIT2% ../libgit2 -G %GENERATOR%
     cmake --build . --config Release --target install
     cd ..
     
-    C:\Python35-x64\Scripts\pip.exe install wheel
+    %PIP% install wheel
-    C:\Python35-x64\python.exe setup.py bdist_wheel 
+    %PYTHON% setup.py bdist_wheel 
   
 artifacts:
 - path: dist\*.whl