Fluid: SIMD for Resize Linear 8UC3

* SIMD for fluid::Resize 8U3C

* Rework horizontal pass + add 8U4C case

* Reproduce stackoverflow test

* StackOverflow test

* SSE42 impl

* SSE42 impl improvement

* GAPI:SSE42 simd opt for Resize 8UC3. Final version

* Fix tests

* Conditional compilation fix

* Applied comments

* Applied comments. Step2

* Applied comments. Step2

GAPI: SIMD optimization for AbsDiffC kernel

* SIMD optimization for AbsDiffC kernel

* Applied comments

* Applying comments and refactoring: Remove new univ intrinsics.

* Performance experiment

* Applied comments.Step2

* Applied comments. Step3

Generic copy kernel

* Moved RMat wrapping of cv::Mats to StreamingInput

* Generalized GCopy kernel

* Generic GCopy kernel: applied review comments

[G-API]: Fluid: add mask, extend convertTo for CV_16S

* Add Fluid `mask` kernel + Acc. and Perf. tests
 - simple cycle implementation with restrictions on mask type and input/output type like in OCV/GPU kernels (mask - CV_8UC1 only, input/output - CV_8UC1, CV_16UC1, CV_16SC1)

* Added convertions from/to 16S

* `convertTo()` perf tests refactoring
 - add testing of `alpha` and `beta` parameters
 - fixed unreliable comparison
 - added instances to OCV, Fluid and GPU tests according to the changes

* Addressing comments
 - fixed multiple-channel mistake - prohibited multiple-channeling

* Reduced perf tests

[G-API]: Add Fluid bitwise operations implementation for (GMat, GScalar)

* Added Fluid `bitwise` with `Scalar` + acc.tests
 - simple loop implementation for Fluid used (no `hal`);
   - `Scalar` is casted to `int` in the beginning
 - tests just modified to work with `Scalar`
 - expected output in operators' tests fixed (operators can't change Mat's depth)
 - `float` `Scalar` `RNG` added, `RNG` reworked (`time` is used now), initialization of test fixtures reworked
   - if input or output is `float` Scalar is initialized by `float`
 - some problems with Fluid/OCV floating-point comparison difference stashed by `AbsSimilarPoints()` usage, FIXME added
 - divide-by-zero is now fixed differently and everywhere

* - Added perf_tests for bitwise_Scalar operations
 - due to errors of Fluid floating-point comparison operations, added support of different validation in Cmp perf_tests; added FIXME

 - reworked integral initialization of Scalar

* Addressing comments
 - NULL -> nullptr
 - Scalar convertion moved to the function
 - avoid -> avoiding

* Addressing comments

* CV_assert -> GAPI_assert

* Addressed DM comments
 - refactored convertScalarForBitwise()
 - removed unnecessary braces for switch

* Changed the operators tests
 - switch via `enum` implemented
 - infrastructure for that refactored

[G-API]: Fluid Core kernels performance tests

* Add performance tests for a list of Fluid Core kernels

* Update gapi_core_perf_tests_fluid.cpp

Addressing a comment