does not build on Ubuntu 16.04

[pavelpetrovic]

0%] Building CXX object CMakeFiles/Moby.dir/src/AABB.cpp.o
[ 1%] Building CXX object CMakeFiles/Moby.dir/src/ArticulatedBody.cpp.o
In file included from /usr/include/unicode/utypes.h:38:0,
from /usr/include/unicode/ucnv_err.h:88,
from /usr/include/unicode/ucnv.h:52,
from /usr/include/libxml2/libxml/encoding.h:31,
from /usr/include/libxml2/libxml/parser.h:810,
from /usr/local/Moby/include/Moby/XMLTree.h:14,
from /usr/local/Moby/src/ArticulatedBody.cpp:10:
/usr/include/unicode/umachine.h:376:13: error: ‘char16_t’ does not name a type
typedef char16_t UChar;

cmake failed to add "-std=c++11" to flags.make