Merge remote-tracking branch 'origin/master' into merge-2.4

Conflicts:
	modules/ocl/src/arithm.cpp

modules/core/include/opencv2/core/cvdef.h

@@ -458,15 +458,8 @@ CV_INLINE int cvIsInf( double value )
 #      define CV_XADD(addr, delta) (int)__sync_fetch_and_add((unsigned*)(addr), (unsigned)(delta))
 #    endif
 #  endif
-#elif (defined WIN32 || defined _WIN32 || defined WINCE) && (!defined RC_INVOKED)
-#  if !defined(_M_AMD64) && !defined(_M_IA64) && !defined(_M_ARM)
-     CV_EXTERN_C __declspec(dllimport) long __stdcall InterlockedExchangeAdd(long volatile *Addend, long Value);
-#    define CV_XADD(addr, delta) (int)InterlockedExchangeAdd((long volatile*)addr, delta)
-#  else
-     CV_EXTERN_C long _InterlockedExchangeAdd (long volatile *Addend, long Value);
-#    pragma intrinsic(_InterlockedExchangeAdd)
-#    define CV_XADD(addr, delta) (int)_InterlockedExchangeAdd((long volatile*)addr, delta)
-#  endif
+#elif defined _MSC_VER && !defined RC_INVOKED
+#  define CV_XADD(addr, delta) (int)_InterlockedExchangeAdd((long volatile*)addr, delta)
 #else
    CV_INLINE CV_XADD(int* addr, int delta) { int tmp = *addr; *addr += delta; return tmp; }
 #endif

modules/core/include/opencv2/core/cvstd.hpp

@@ -364,6 +364,10 @@ public:
     String& operator=(const char* s);
     String& operator=(char c);
 
+    String& operator+=(const String& str);
+    String& operator+=(const char* s);
+    String& operator+=(char c);
+
     size_t size() const;
     size_t length() const;
 
@@ -416,6 +420,7 @@ public:
     String(const std::string& str);
     String(const std::string& str, size_t pos, size_t len = npos);
     String& operator=(const std::string& str);
+    String& operator+=(const std::string& str);
     operator std::string() const;
 
     friend String operator+ (const String& lhs, const std::string& rhs);
@@ -544,6 +549,27 @@ String& String::operator=(char c)
     return *this;
 }
 
+inline
+String& String::operator+=(const String& str)
+{
+    *this = *this + str;
+    return *this;
+}
+
+inline
+String& String::operator+=(const char* s)
+{
+    *this = *this + s;
+    return *this;
+}
+
+inline
+String& String::operator+=(char c)
+{
+    *this = *this + c;
+    return *this;
+}
+
 inline
 size_t String::size() const
 {

modules/core/include/opencv2/core/cvstd.inl.hpp

@@ -103,6 +103,13 @@ String& String::operator = (const std::string& str)
     return *this;
 }
 
+inline
+String& String::operator += (const std::string& str)
+{
+    *this = *this + str;
+    return *this;
+}
+
 inline
 String::operator std::string() const
 {