Drop range-and-a-half algorithm overloads

[cjdb]

All of the input-range-and-a-half algorithms are deprecated in the Ranges TS, and MSVC doesn't recognise this flag.

We could add some fancy CMake to accommodate this, but these overloads aren't even in C++20 (unless I'm missing something). I think the solution is to drop the algorithms.

[CaseyCarter]

I'm having trouble connecting the issue title with the discussion to determine exactly what the problem is. I suspect you're not actually suggesting that we should add -Wno-deprecated-declarations to MSVC. 😉