Mesa (12.0): appveyor: Install pywin32 extensions.

[Jose Fonseca]

Module: Mesa
Branch: 12.0
Commit: 53e8701c7b01407787121269d2849c400d2273ee
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=53e8701c7b01407787121269d2849c400d2273ee

Author: Jose Fonseca <jfonseca at vmware.com>
Date:   Thu Aug 11 14:00:35 2016 +0100

appveyor: Install pywin32 extensions.

AppVeyor build images seem to have been upgraded to Python 2.7.12, but
no longer have pywin32 pre-installed.

---

 appveyor.yml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/appveyor.yml b/appveyor.yml
index 2e9b9d6..2618f69 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -47,6 +47,8 @@ install:
 - python -m pip --version
 # Install Mako
 - python -m pip install --egg Mako
+# Install pywin32 extensions, needed by SCons
+- python -m pip install pypiwin32
 # Install SCons
 - python -m pip install --egg scons==2.4.1
 - scons --version