Adding support for WinRT(WinPhone 8/8.1 and Win Store) via CMake 3.1

- Substituted HAVE_WINRT with WINRT
- Fixed compilation issues in ocl.cpp and parallel.cpp
- Fixed compiler issue for WP8: "C2678: binary '+' : no operator found which takes a left-hand - Fixed gitignore
- Added #ifdef HAVE_OPENCL to remove compiler warnings in ocl.cpp
- Used NO_GETENV similar to '3rdparty\libjpeg\jmemmgr.c;
- Added ole32.lib for core module (for WindowsStore 8.0 builds)
- Made OpenCV_ARCH aware of ARM

Signed-off-by: Maxim Kostin <v-maxkos@microsoft.com>

modules/core/src/ocl.cpp

@@ -64,7 +64,15 @@
 // TODO Move to some common place
 static bool getBoolParameter(const char* name, bool defaultValue)
 {
+/*
+ * If your system doesn't support getenv(), define NO_GETENV to disable
+ * this feature.
+ */
+#ifdef NO_GETENV
+    const char* envValue = NULL;
+#else
     const char* envValue = getenv(name);
+#endif
     if (envValue == NULL)
     {
         return defaultValue;
@@ -85,7 +93,7 @@ static bool getBoolParameter(const char* name, bool defaultValue)
 // TODO Move to some common place
 static size_t getConfigurationParameterForSize(const char* name, size_t defaultValue)
 {
-#ifdef HAVE_WINRT
+#ifdef NO_GETENV
     const char* envValue = NULL;
 #else
     const char* envValue = getenv(name);
@@ -728,7 +736,7 @@ static void* initOpenCLAndLoad(const char* funcname)
     static HMODULE handle = 0;
     if (!handle)
     {
-#ifndef HAVE_WINRT
+#ifndef WINRT
         if(!initialized)
         {
             handle = LoadLibraryA("OpenCL.dll");
@@ -2190,6 +2198,7 @@ inline cl_int getStringInfo(Functor f, ObjectType obj, cl_uint name, std::string
     return CL_SUCCESS;
 }
 
+#ifdef HAVE_OPENCL
 static void split(const std::string &s, char delim, std::vector<std::string> &elems)
 {
     elems.clear();
@@ -2230,8 +2239,9 @@ static bool parseOpenCLDeviceConfiguration(const std::string& configurationStr,
     }
     return true;
 }
+#endif
 
-#ifdef HAVE_WINRT
+#ifdef WINRT
 static cl_device_id selectOpenCLDevice()
 {
     return NULL;