Fix appveyor build for Windows x86

- platform should remain "Win32" for appveyor's scripts to execute
successfully
- Finding middle ground between clang and MSVC

appveyor.yml

@@ -7,7 +7,7 @@ environment:
   BUILD_DIR: "%APPVEYOR_BUILD_FOLDER%/build"
 
 platform:
-  - x86
+  - Win32
   - x64
 
 configuration:

deps.bat

@@ -2,7 +2,8 @@
 
 set SRC_DIR=%~dp0
 
-if not defined platform set platform=x86
+if not defined ARCH set ARCH=x86
+if defined platform if "%platform%"=="x64" set ARCH=x64
 
 @rem init/update submodules
 cd %SRC_DIR%
@@ -16,7 +17,7 @@ git submodule update --init
 
 cd %SRC_DIR%deps\libuv
 @rem the arguments to vcbuild make all the difference to further builds
-call vcbuild.bat release %platform% shared
+call vcbuild.bat release %ARCH% shared
 
 if "%msbuild_platform%"=="x64" (
     set CMAKE_GENERATOR_NAME=Visual Studio 14 2015 Win64

src/uvw/stream.hpp

@@ -171,9 +171,13 @@ class StreamHandle: public Handle<T, U> {
     }
 
 protected:
+#ifdef _WIN32
 	StreamHandle(std::shared_ptr<Loop> ref) noexcept
         : Handle{std::move(ref)}
     { }
+#else
+    using Handle<T, U>::Handle;
+#endif
 
 public:
     /**