Remove DISTUTILS_USE_SDK from 32-bit builds.

Author: Lukasa

appveyor.yml

@@ -37,19 +37,16 @@ environment:
     - TOOLCHAIN_VERSION: 14.0
       RUST: 1.8.0
       PYTHON: "C:\\Python34"
-      DISTUTILS_USE_SDK: "1"
       platform: Win32
 
     - TOOLCHAIN_VERSION: 14.0
       RUST: beta
       PYTHON: "C:\\Python34"
-      DISTUTILS_USE_SDK: "1"
       platform: Win32
 
     - TOOLCHAIN_VERSION: 14.0
       RUST: nightly
       PYTHON: "C:\\Python34"
-      DISTUTILS_USE_SDK: "1"
       platform: Win32
 
     - TOOLCHAIN_VERSION: 14.0
@@ -73,19 +70,16 @@ environment:
     - TOOLCHAIN_VERSION: 14.0
       RUST: 1.8.0
       PYTHON: "C:\\Python33"
-      DISTUTILS_USE_SDK: "1"
       platform: Win32
 
     - TOOLCHAIN_VERSION: 14.0
       RUST: beta
       PYTHON: "C:\\Python33"
-      DISTUTILS_USE_SDK: "1"
       platform: Win32
 
     - TOOLCHAIN_VERSION: 14.0
       RUST: nightly
       PYTHON: "C:\\Python33"
-      DISTUTILS_USE_SDK: "1"
       platform: Win32
 
     - TOOLCHAIN_VERSION: 14.0