multi3d compilation on windows?

Author: Teseo Schneider

.appveyor.yml

@@ -30,10 +30,11 @@ install:
 build:
   parallel: true
 build_script:
+  - "MSBuild /help"
   - "SET PATH=%PYTHON%;%PYTHON%\\Scripts;%PATH%"
   - cd c:\projects\polyfempy
   - "python --version"
-  - python -m pip install . --no-deps -vv
+  - python setup.py install
 
 test_script:
   - cd c:\projects\polyfempy

setup.py

@@ -60,7 +60,7 @@ def build_extension(self, ext):
             cmake_args += ['-DCMAKE_LIBRARY_OUTPUT_DIRECTORY_{}={}'.format(cfg.upper(), extdir)]
             if sys.maxsize > 2**32:
                 cmake_args += ['-A', 'x64']
-            build_args += ['--', '/m', '/MP']
+            build_args += ['--', '/m']
         else:
             cmake_args += ['-DCMAKE_BUILD_TYPE=' + cfg]
             build_args += ['--', '-j2']