core: add an ability to use cxx11 lambda as a parallel_for_ body

doc/tutorials/core/how_to_use_OpenCV_parallel_for_/how_to_use_OpenCV_parallel_for_.markdown

@@ -153,7 +153,7 @@ The first thing is to declare a custom class that inherits from @ref cv::Paralle
 `virtual void operator ()(const cv::Range& range) const`.
 
 The range in the `operator ()` represents the subset of pixels that will be treated by an individual thread.
-This splitting is done automatically to distribuate equally the computation load. We have to convert the pixel index coordinate
+This splitting is done automatically to distribute equally the computation load. We have to convert the pixel index coordinate
 to a 2D `[row, col]` coordinate. Also note that we have to keep a reference on the mat image to be able to modify in-place
 the image.
 
@@ -167,6 +167,11 @@ nstripes parameter in @ref cv::parallel_for_. For instance, if your processor ha
 or setting `nstripes=2` should be the same as by default it will use all the processor threads available but will split the
 workload only on two threads.
 
+@note
+C++ 11 standard allows to simplify the parallel implementation by get rid of the `ParallelMandelbrot` class and replacing it with lambda expression:
+
+@snippet how_to_use_OpenCV_parallel_for_.cpp mandelbrot-parallel-call-cxx11
+
 Results
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