build: add RING_UWP flag

Change-Id: I691900dbbe01dc5181931f9b87e8f72f1fb67ce6
Tuleap: #790

ring-client-uwp.vcxproj

@@ -142,7 +142,7 @@
       <AdditionalOptions>/bigobj %(AdditionalOptions)</AdditionalOptions>
       <DisableSpecificWarnings>4453;28204;4267;4129;4973;4018;</DisableSpecificWarnings>
       <AdditionalIncludeDirectories>contrib\qrencode-win32;..\ring-daemon\MSVC;..\ring-daemon\src\media;..\ring-daemon\src;..\ring-daemon\src\dring;..\ring-daemon\contrib\include;..\ring-daemon\contrib\include\pjlib;..\ring-daemon\contrib\pjproject\third_party\speex\include;%(AdditionalIncludeDirectories)</AdditionalIncludeDirectories>
-      <PreprocessorDefinitions>STATICLIB;WIN32_NATIVE;_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
+      <PreprocessorDefinitions>STATICLIB;RING_UWP;WIN32_NATIVE;_UNICODE;UNICODE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
       <WholeProgramOptimization>false</WholeProgramOptimization>
       <CompileAsWinRT>true</CompileAsWinRT>
     </ClCompile>

ring-client-uwp.vcxproj.filters

@@ -80,6 +80,7 @@
     <ClCompile Include="Ringtone.cpp">
       <Filter>Media\Audio</Filter>
     </ClCompile>
+    <ClCompile Include="AboutPage.xaml.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="LoadingPage.xaml.h" />
@@ -156,6 +157,7 @@
     <ClInclude Include="Ringtone.h">
       <Filter>Media\Audio</Filter>
     </ClInclude>
+    <ClInclude Include="AboutPage.xaml.h" />
   </ItemGroup>
   <ItemGroup>
     <Image Include="Assets\AccountTypeRING.png">