Replace deprecated std functions

I stumbled across some uses of standard library lib features that have been deprecated since C++11 and are now actually gone from Clang 5 in C++17 mode, so this MR just replaces them with their direct successors.

enabled an automatic merge when the pipeline for 4d35dc0f succeeds

merged

mentioned in commit 99907ad2

While you replaced the old functions literally by their modern analogues, wouldn't it be nicer to use a range-for instead of std::for_each with a std::mem_fn? At least for non-optimized code this will also be faster, because std::mem_fn introduces an indirection via a member function pointer.

That's true - I didn't put a lot of thought into the fix, I just wanted clang to compile the module

I can prepare a fix, but I cannot test despite running the dune-istl checks, because I never use this code.

TBH, I don't use the stuff in overlappingschwarz.hh either, but clang trips over it even without instantiating, and I figured the fix was sufficiently trivial. But plugging in some range-based for loops is probably not really controversial, either.

ranges based for sonds like the better alternative.

mentioned in merge request !117 (merged)