DM-29501: replace unary_function, binary_function, deprecated in C++17

[mwittgen]

No description provided.

[erykoff]

So the changes are good so far, but I fear that they are incomplete, in particular regarding Integrate.h and friends. I can't comment on the non-diff code, so I have links here.
The basic problem is that there are two different interrelated code-paths here. First, we have integrate which is a front-end for int1d; integrate2d which does a double loop over integrate. As best as I can tell, this is the code path that is used in the stack and all the tests (except for the one example that has been commented out).
Second, we have int2d and int3d which (a) aren't used; (b) aren't tested; (c) aren't updated. (In particular,

afw/include/lsst/afw/math/Integrate.h

Lines 646 to 664 in e607ee5

	/**
	* Helpers for constant regions for int2d, int3d:
	*
	*/
	template <class T>
	struct ConstantReg1 : public std::unary_function<T, IntRegion<T> > {
	ConstantReg1(T a, T b) : ir(a, b) {}
	ConstantReg1(IntRegion<T> const &r) : ir(r) {}
	IntRegion<T> operator()(T) const { return ir; }
	IntRegion<T> ir;
	};
	template <class T>
	struct ConstantReg2 : public std::binary_function<T, T, IntRegion<T> > {
	ConstantReg2(T a, T b) : ir(a, b) {}
	ConstantReg2(IntRegion<T> const &r) : ir(r) {}
	IntRegion<T> operator()(T x, T y) const { return ir; }
	IntRegion<T> ir;
	};

are not going to compile with c++17 but aren't used so don't fail tests).
Relatedly, there is code comment documentation

afw/include/lsst/afw/math/Integrate.h

Lines 144 to 165 in e607ee5

	// Two- and Three-Dimensional Integrals:
	//
	// These are slightly more complicated. The easiest case is when the
	// bounds of the integral are a rectangle or 3d box. In this case,
	// you can still use the regular IntRegion. The only new thing then
	// is the definition of the function. For example, to integrate
	// int(3x^2 + xy + y , x=0..1, y=0..1):
	//
	// struct Integrand :
	// public std::binary_function<double,double,double>
	// {
	// double operator()(double x, double y) const
	// { return x*(3.*x + y) + y; }
	// };
	//
	// integ::IntRegion<double> reg3(0.,1.);
	// double integ3 = int2d(Integrand(),reg3,reg3);
	//
	// (Which should give 1.75 as the result.)
	//
	//
	//

that is now out of date, and furthermore refers to the code path that isn't actually used so has been out of date for some untold years.

My thought would be to remove the incorrect documentation and the unused, untested, and probably broken anyway int2d and int3d code paths and friends (but of course leave int1d which is used by integrate and integrate2d).

[erykoff]

Looks good, with all the dead code that I know of now removed. Thanks!
All good assuming that this compiles and tests pass with both C++14 and C++17.