Werner compil warning (#32)

* Replace int by size_t in for loops.

* Various dtor missing and some other warning fixes.

* fixed size_t vs int

* fixed size_t vs int

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Co-authored-by: Paddle <PaddleStroke@users.noreply.github.com>
Co-authored-by: Aik-Siong Koh <askoh@askoh.com>

OndselSolver/DifferenceOperator.cpp

@@ -18,7 +18,7 @@ using namespace MbD;
 
 FRowDsptr DifferenceOperator::OneOverFactorials = []() {
 	auto oneOverFactorials = std::make_shared<FullRow<double>>(10);
-	for (int i = 0; i < oneOverFactorials->size(); i++)
+	for (size_t i = 0; i < oneOverFactorials->size(); i++)
 	{
 		oneOverFactorials->at(i) = 1.0 / std::tgamma(i + 1);
 	}