update #10255 - disable atomics when header file missing

Trac Comment 1 by —2013-07-24T21:07:04.545Z

Feel free to reassign ticket to yourself if you want to make other updates.

Trac Comment 4 by —2013-08-01T21:40:23.705Z

Adjusted the config test to run with -std=C++11. Otherwise it would never succeed with compiling #include <atomic>.

Also rearranged (and hopefully simplified) the #if chain in putilimp.h. There's no longer a need for special case Macintosh tests - the autoconf test handles it correctly.