Break compatiblity with C++98, require C++11 as mininum.

8 jobs for make_unique in 8 minutes and 28 seconds
Status Job ID Name Coverage
  Test
passed #16563
VS2013
VS2013-32-bit

00:00:51

passed #16562
VS2013
VS2013-64-bit

00:00:58

passed #16561
VS2015
VS2015-32-bit

00:01:05

passed #16560
VS2015
VS2015-64-bit

00:01:11

passed #16557
Linux
clang-c++11

00:02:18

passed #16559
Linux
cppcheck

00:01:48

passed #16556
Linux
gcc-c++11

00:03:49

passed #16558
Apple
macos-c++11

00:02:28